useKeyboardHandler
useKeyboardHandler
is a hook that offers low-level but more powerful API in comparison to useKeyboardAnimation
. Using this hook you are getting an access to keyboard lifecycle events and you can easily determine the moment of the beginning animation, the end of the animation and get keyboard position in every frame of the animation.
Example​
useKeyboardHandler(
{
onStart: (e) => {
"worklet";
},
onMove: (e) => {
"worklet";
},
onInteractive: (e) => {
"worklet";
},
onEnd: (e) => {
"worklet";
},
},
[],
);
Don't forget to add worklet
directive to all onStart
/onMove
/onInteractive
/onEnd
handlers. Otherwise your code will throw exception.
These handlers are not workletized by default, since it's not a part of reanimated
package.
Since onMove
handler on iOS is based on CADisplayLink
usage - you may need to add following content in Info.plist
if you want to have your animations running at 120 FPS on devices with ProMotion displays:
+ <key>CADisableMinimumFrameDurationOnPhone</key>
+ <true/>
Event structure​
height
- height of the keyboard;progress
- a value between0
(closed) and1
(opened) indicating relative keyboard position;duration
- duration of the animation;target
- tag of the focusedTextInput
(or-1
if the tag is not found).
Handlers​
onStart
​
This function is called before the keyboard movement starts.
height
and progress
values will have
destination values, i. e. if keyboard was closed but will appear -
these values will have a values like "keyboard is already opened"
(progress
will be equal to 1
and
height
will have non-zero value).
useKeyboardHandler(
{
onStart: (e) => {
'worklet';
const willKeyboardAppear = e.progress === 1;
}
},
[]
);
useKeyboardHandler(
{
onStart: (e) => {
'worklet';
const willKeyboardAppear = e.progress === 1;
}
},
[]
);
onMove
​
This function will be called every frame when the keyboard changes its position.
useKeyboardHandler(
{
onMove: (e) => {
'worklet';
progress.value = e.progress;
height.value = e.height;
}
},
[]
);
useKeyboardHandler(
{
onMove: (e) => {
'worklet';
progress.value = e.progress;
height.value = e.height;
}
},
[]
);
There is no corresponding events in iOS for this hook. So values will not be perfectly synchronized with the keyboard.
The same is applied to Android < 11 - these OS versions don't have API for getting keyboard positions during an animation.
onInteractive
​
This function will be called every frame when user changes position of the keyboard by the drag.
If finger is released and keyboard animates to its final destination, then
the standard onStart
/onMove
/onEnd
life cycles will be triggered.
useKeyboardHandler(
{
onInteractive: (e) => {
'worklet';
progress.value = e.progress;
height.value = e.height;
}
},
[]
);
useKeyboardHandler(
{
onInteractive: (e) => {
'worklet';
progress.value = e.progress;
height.value = e.height;
}
},
[]
);
This event is available only on Android >= 11. To receive it you need to use KeyboardGestureArea.
On iOS you need to specify keyboardDismissMode="interactive"
on your ScrollView
.
onEnd
​
This function will be called when the keyboard has completed its movement. The event will contain current keyboard metrics.
useKeyboardHandler(
{
onEnd: (e) => {
'worklet';
progress.value = e.progress;
height.value = e.height;
}
},
[]
);
useKeyboardHandler(
{
onEnd: (e) => {
'worklet';
progress.value = e.progress;
height.value = e.height;
}
},
[]
);