SLIDING LEAF WITH DETACHABLE LOCK The invention refers to sliding leaves for windows doors or other sliding leaves with handle and lock. The invention further refers to a method of mounting and assembling sliding leaves on partition panels, such as walls. Document EP 3865644 discloses a sliding leaf with handle and a control. The control moves in a cavity configured in the handle. An object of the invention is a sliding leaf with a lock. A further object of the invention is a sliding leaf with a lock, which can be placed after the installation of the sliding leaf. A further object of the invention is a sliding leaf with a lock, which operates and moves without problem between the position in which the leaf is locked and the position in which it is unlocked. The object of the invention is also a lock with a handle for a sliding leaf. A further object of the invention is a sliding leaf that cannot be forcibly lifted from its guide. A further object of the invention is a sliding leaf that guarantees a flawless connection with the stationary frame that surrounds it. The invention is defined in independent claims. The dependent claims define features that offer further advantages to invention. A stile for a sliding leaf has an elongated profile with a length extending along the longitudinal direction, a movable locking plate, an elongated detachable handle and a lock with a tongue. The profile has two longitudinal parallel channels, i.e. a first channel and a second channel, along the longitudinal direction. The handle is fitted to the first channel between one end of the lock and a trolley that is provided in the first channel. The lock is attached with its tongue to the trolley and is configured to be detachable from the trolley. The locking plate is connected to the tongue and is movable within the second channel. The housing of the trolley within a channel of stile on one hand and configuration of the lock and the tongue that is connected to both the trolley and the locking plate on the other, offers a robust structure with a reliable operation between the locking and unlocking position. In some examples the tongue passes through a hole provided in the handle. In some embodiments the tongue may penetrate a hole, which is provided in the trolley. This further stabilizes the motion of the tongue and the trolley and further facilitates the attachment and detachment of the lock to and from the trolley respectively. In some examples the trolley has means, such as balls, flexible plates or other, which facilitate its motion on the first channel of the stile. The tongue may be elongated with its length being measured along the longitudinal direction of the stile. The first channel and the second channel of the stile may communicate with a third channel provided in between. In some examples there is a carrier in the third channel which is connected to both the tongue and the locking plate. This configuration of the lock, the trolley and the locking plate offers a firm connection and a stable transfer of the motion of the lock to the locking plate. In some examples, the locking plate has a switch that operates between two positions. In one position the locking plate moves freely and in the other position the locking plate cannot move. The switch allows, for example, the user to move the locking plate when the sliding leaf is in contact with the fixed casement and closes the opening and immobilizes the locking plate when the sliding leaf is open. The switch, which may be employed with any sliding leaf with a locking plate secures the locking plate in a fixed position, for example during transportation, assembly and other. In some examples of the switch, the switch has a neck and a base with a cross-section area greater than the cross-section area of the neck. The switch may operate within a slot extending along the locking plate and having a variable width. In some examples the stile has two detachable handles mounted on opposite sides of the stile, for example one operating from the inside and one from the outside. The profile of the stile may be an aluminum profile. In some examples the profile is a composite profile with sections of aluminum and a section or sections of thermal insulation material. In some examples the handle is made of aluminum. A sliding leaf has a stile with a handle, which is located between two parallel profiles. In some examples the handle covers or almost covers the length of the stile between the two parallel profiles. A sliding leaf is associated with a fixed frame. In some examples, the fixed frame has an adjustable profile associated with the locking plate. The adjustable profile has at least one adjustment means that adjusts the distance between the adjustable profile and the locking plate. Such adjustable profile may be aligned with the locking plate to secure locking. Alignment is effected either when the locking plate is perfectly straight or if it is slightly curved, since the adjustable profile, otherwise “floating profile”, has certain flexibility. In some examples, the adjustment means may include a nut and a screw moving inside that nut. Either the nut or the screw is attached to the adjustable profile. An assembly for a stile of a sliding leaf according to the invention has an elongated handle with an elongated leg with a longitudinal hole, a lock and a trolley. The lock has one tongue firmly attached to the lock, which passes through the hole and immobilized in a carriage, so that handle is between one end of the lock and the trolley. The tongue of the lock and the hole of the handle have dimensions that allow the lock to move along the handle. The invention further suggests a sliding leaf, having a stile between two parallel profiles. The stile has an elongated profile with a length extending along the longitudinal direction and a detachable and longitudinal handle attached to the profile, with the handle covering or almost covering the length of the stile between the two parallel profiles. The invention further suggests a system with a sliding leaf having a locking plate and a fixed frame associated with the sliding leaf. The fixed frame has one body and an adjustable profile associated with the locking plate. The adjustable profile has at least one adjustment element configured to adjust the distance of the adjustable profile from the locking plate, so that the adjustable profile is aligned with the locking plate. Advantages of embodiments that are according with the invention are described below: ^ It facilitates the transportation of the sliding leaves without the handle and lock, which may cause damage to adjacent leaves when they are mounted on the leaves during transportation. ^ The invention offers the possibility to easily assemble the sliding leaf in situ, before or after mounting it on the fixed frame. ^ It facilitates the replacement of the handle and lock, for example in case of damage. ^ The handle extends to the entire height of the leaf so when the lead is installed, it cannot be detached from it and does not allow the leaf to be forcibly extracted. In situ, any attempt to remove the leaf from the fixed frame is prevented by the edge of the opening of the partition, on which the fixed frame is placed, and/or by the fixed frame as such. ^ The invention allows adjustment during installation and operation so that the locking sliding plate of the sliding leaf is aligned with the cooperating profile of the fixed frame. Adjustment is made possible by adjustment means, e.g. by screws adjusting the position of the vertical face of the fixed frame, which receives the lock(s), mushroom(s) or barrel(s) of the locking sliding plate. ^ It provides a flawless motion of the lock during locking and unlocking, as it remains aligned within the channel, where the lock is housed. ^ The detachable handle is functional without limiting the view through the glass pane. ^ The lock(s) may be used on one side or on both sides of the sheet. ^ The switch that is mounted on the sash co-operates protects the sliding plate from damage, immobilizes it during transportation and makes assembly easy and fast. ^ The trolley that fits within the channel of the stile facilitates the assembly. Examples of the invention are described below with reference to the following Figures: Figure 1 shows the profile, the locking plate and the lock disassembled Figure 2 shows the cross-section of the profile and the handles Figure 3 shows the contact of the sliding leaf and the fixed frame Figure 4 shows a perspective view of elements of the lock disassembled Figure 5 shows a perspective view of elements of the lock from another angle Figure 6 shows elements of the locking plate Figure 7 shows the locking plate Figure 8 shows the vertical element of the fixed profile and the and the adjustment profile disassembled Figure 9 shows the adjustment means of the distance of the adjustable profile and the fixed frame Figure 10shows the cross-section of the vertical elements of the fixed frame with the adjustable profile Figure 11shows the cross-section of the vertical elements of the fixed frame with the adjustable profile and the stile at a distance, with the adjustment means Figure 12shows the cross-section of the vertical elements of the fixed frame with the adjustment means disassembled Figure 3 shows the sliding leaf 21 of a door, separating two spaces, for example an inner space and an outer space. In the example, the leaf 21 has a double glazing 85 and a surrounding frame, i.e. the sash. The surrounding frame has vertical stiles (uprights) and horizontal profiles, i.e. the lower profile and the upper profile, which connect the stiles to each other. The sliding leaf 21 slides or rolls on a bottom guide and a top guide of a casement, i.e. the fixed frame, which is provided around the opening of a partition, such as a wall. Each stile has a profile 71, which on one inner face has seats to receive the edges of the glazing 85. On either side of the inner face, the profile has channels. Two handles 61, 62 provided in each one of the two channels facilitate the user to draw the sliding leaf 21, see Figure 2. One of the handles 61, 62, i.e. the inner handle 61, is in the inner space and the other handles 61, 62, i.e. the outer handle 62, is in the outer space. The inner handle 61 extends almost along all the length of profile 71 and covers almost all the height of the opening covered by the sliding leaf 21. Due to its length, the inner handle 61 prevents the sliding leaf 21 from being lifted from the bottom guide of the casement and disengaged from it. The outer handle 62 is preferably of the same length and covers almost all the height of the opening covered by the door. The inner handle 61 has an elongated central section with Π-shaped cross- section and an elongated protruding section with angle-shaped cross-section (Γ- shaped). The central section fits within the channel of the stile. The protruding section is accessible by the user and facilitates the user to operate the sliding leaf 21. The central section has a central leg and two side legs. The two side legs are connected to the sides of the channel of the stile by appropriate means of connection, e.g. screws, rivets or others. As shown schematically in Figure 1, Figure 4 and Figure 5, the sliding leaf 21 has a lock 31 with a tongue 33. The tongue 33 passes through a hole provided in the central leg of the central section of the handle 61. The tongue 33 of the lock 31 of the example is elongated and fits and immobilized in a hole 44 of a similar shape with the tongue 33 of a trolley 41. Trolley 41 can move within the channel of the stile, where handle 61 is installed. Sliding or rolling of the trolley 41 within the channel is facilitated by appropriate means, e.g. balls 47, flexible plates 46 or other. Immobilizing the lock 31 in the trolley 41 is achieved by connecting means 39, 49. In the example of Figure 5, the connecting means are screws 49 that penetrate into suitable sockets, e.g. cavities 39, of tongue 33. The lock 31 can be immobilized relative to handle 61 using a key 48, which operates the pin 481. The tongue 33 of the lock 31 of the example is rectangular or approximately rectangular in shape and has a dimension perpendicular to the plane of the glazing 85 larger than the depth of the channel. As the tongue 33 exits the hole 44 of the trolley 41, it penetrates the bottom of the channel and enters the central space 72 of the profile 71 of the stile. The central space 72 houses a slidable carrier 93 of locking plate 91. The carrier 93 of the locking plate 91 is firmly connected with the tongue 33 of the lock 31 with a connector, e.g. screws in holes. The connection of the lock 31, the trolley 41, the slidable carrier 93 and the locking plate 91 is robust and transfers the movement of the lock 31 to the locking plate 91. As an example, the layout is shown schematically in Figure 1 and in Figures 4 – 7. The Figures show the trolley 41 and the carrier 93, which are firmly attached to the tongue 33, with the trolley 41 located between one end of the lock 31 and the carrier 93. The sliding locking plate 91 moves in a further channel 77 of the profile 71 of the stile, which is located in the outer side of the stile, i.e. opposite and extending parallel or almost parallel to its inner face. The carrier 93 passes through a hole shaped at the back of the profile 71, whose dimensions allow the movement of the carrier 93 along the profile. In the particular embodiment of Figure 2 the profile 71 has two channels on either side of the inner face that house the handles 61 and 62, one central space 72, i.e. a channel with the carrier 93 and a channel 77 with the locking plate 91 communicating with the central space 72. In the example that is shown in Figure 1 and Figure 7, the sliding locking plate 91 has two sections, i.e. a top section 911 and a bottom section 912. Between these two sections, there are the carrier 93 and an element 95 with one slot 96. Slot 96 is elongated with a variable width and extends along the longitudinal direction of profile 71. As an example, slot 96 has a T-shape. On the back of element 95, between element 95 and profile 71, there is a switch 81 connected to the profile 71. The switch 81 has a body 84, which is firmly attached to the profile 71 and a knob 82 that is pushed toward the slot 96 by a spring 88 acting between the body 84 and the knob 82. In the example of Figure 7, the knob 82 has a base 86, a head 89 and a neck 87 between the base 86 and the head 89. The neck 87 and the head 89 have a cross section smaller than that base 86 and may move unimpeded into the slot 96. The base 86 has a cross section with such dimensions, so than when the base 86 is in the widest part of the slot 96, the base 86 is trapped in the slot 96 and cannot move along the slot 96 and consequently along the profile 71. When the door is closed, the knob 82 is pressed by the fixed frame surrounding the opening and the neck 87 is inside the slot 96. In this position, the sliding locking plate 91 and the lock 31 move freely along the profile 71. When the stile is not in contact with the fixed frame than surrounds the opening, spring 88 pushes base 86 of knob 82 within slot 96. In this position, the knob 82 is trapped into slot 96 and does not allow the sliding locking plate 91 and the lock 31 to move. In this way the sliding locking plate 91 is prevented from moving, it remains in a fixed position along the profile 71, always aligned in the appropriate position and consequently allowing the stile to come into contact with the fixed frame unhindered. Locking of the sliding leaves 21 on the fixed frame is achieved by engaging the locking plate 91 on the fixed frame, through cooperating the elements of the locking plate 91, such as mushrooms barrels or other, and the fixed frame. To facilitate the hassle-free cooperation between them, the fixed frame has an adjustable profile 107. The adjustable profile 107 has an elongated leg, which may extend almost all the distance between the guides of the fixed frame. The fixed frame has at least one element to adjust the distance of the adjustable profile 107 from the locking plate 91, so that the two components, adjustable profile 107 and locking plate 91, are in parallel or almost parallel disposition. The fixed frame and τhe element to adjust the distance are shown in Figure 8 and Figure 12. Τhe adjustable profile 107 has a U-section with a channel and a cap 102 fitted thereon. A nut 104, with a hole in which a screw 105 is screwed, is fitted in the channel, between body 108 and adjustable profile 107. The nut 104 with the screw 105 adjusts the distance of the adjustable profile 107 from the body 108 of the fixed frame using a tool 109. The screw 105 is partially placed outside the channel of the adjustable profile 107, with its head resting on the body 108 of the fixed frame and penetrating the hole of the nut 104 from a hole provided at the bottom of the channel of the adjustable profile 107 – see Figure 12. Preferably two or more nuts 104 are installed on the adjustable profile. With such a configuration, the adjustable profile 107 operates a "floating profile" and regulates its distance in relation to the body 108 of the fixed frame. Screw 106 secures the relative position between body 108 and adjustable profile 107. For the assembly of the fixed frame, the adjustable profile 107 may be telescopically received into suitable sockets in a channel of the body 108 of the fixed frame. Their connection can be facilitated by a lip protruding from the edge of the channel of the adjustable profile 107. Such a configuration of the adjustable profile 107 is presented as an example and alternatively other adjustment devices of the adjustable profile 107 may be used. For example, the nut 104 can be adjusted to the body 108 of the fixed frame and the screw 105 can be located within the channel of the adjustable profile 107. The assembly of the fixed frame and the sliding leaves in the opening of a partition, e.g. a wall, may be performed as follows: a) the fixed frame is placed at the edges of the opening, b) the sliding leaf is assembled, without the handle and the lock. The transport of the assembled sliding leaf without the handle and key facilitates handling and transport, as there are no protruding elements, c) the sliding leaf is placed on the fixed frame, d) the handle is assembled with the lock, with the handle between the lock and the trolley, e) the assembled lock-handle system is fitted in the stile and the lock is connected to the stile by appropriate means of connection, which are not accessible when the sliding leaves is in a closed position, i.e. when the opening of the partition is closed, f) the tongue of the lock is connected to the locking plate. As the safety mechanism with the switch is activated, i.e. the head of the knob is not pressed, the locking plate is in a fixed position and the joint of the tongue of the lock and cable carrier is made unobstructed and easily, g) the floating profile of the casement is adjusted so as to be aligned with the locking plate. When the sliding leaf is in a position where the head of the knob is free and not pressed, the locking plate is secured and the lock cannot be moved. When the head is pressed, for example when the sliding leaf closes the opening of the partition, the user can move the lock from one position to another. In this closed position of the sliding leaf, it is impossible to detach the handle and the lock, because there is no access to the means of connection, while at the same time the leaf cannot be lifted from the guide by force, as the handle is prevented from moving from the contour of the opening. Elements of the examples shown in the Figures 21: sliding leaf 31: lock 33: tongue of the lock 39, 49: cooperating connecting means connecting lock 31 and trolley 41 41: trolley 44: hole (opening) in the trolley 41 46: flexible plates on trolley 41 47: rollers on trolley 41 48: key 481: pin 61, 62: handles 71: profile of stile 72: central space, third channel of profile 71 77: channel located in the outer side of the stile, second channel of profile 71 85: glazing 91: locking plate 93: carrier 911: top section, locking plate component 912: bottom section, locking plate component 95: element of locking plate, cooperating with switch 81 96: slot 81: switch 82: knob of switch 81 84: body of switch 81 86: base of knob 82 87: neck of knob 82 88: spring 89: head of knob 81 102: cap 104: adjusting nut 105: adjusting screw 106: fastener that secures adjustable profile 107 to body 108 107: adjustable profile 108: body of fixed frame body 109: tool