您现在的位置是:网站首页> 内容页

Android开发 - 获取系统输入法高度的正确姿势

  • 手机公海最正规的赌船
  • 2019-06-21
  • 84人已阅读
简介问题与解决在Android应用的开发中,有一些需求需要我们获取到输入法的高度,但是官方的API并没有提供类似的方法,所以我们需要自己来实现。查阅了网上很多资料,试过以后都不理想。比如有

问题与解决

在Android应用的开发中,有一些需求需要我们获取到输入法的高度,但是官方的API并没有提供类似的方法,所以我们需要自己来实现。

查阅了网上很多资料,试过以后都不理想。

比如有的方法通过监听布局的变化来计算输入法的高度,这种方式在Activity的配置中配置为"android:windowSoftInputMode="adjustResize""时没有问题,可以正确获取输入法的高度,因为布局此时确实会动态的调整。

但是当Activity配置为"android:windowSoftInputMode="adjustNothing""时,布局不会在输入法弹出时进行调整,上面的方式就会扑街。

不过经过一番探索和测试,终于发现了一种方式可以在即使设置为adjustNothing时也可以正确计算高度放方法。

同时也感谢这位外国朋友:GitHub地址

其实也就两个类,我也做了一些修改,解决了一些问题,这里也贴出来:

KeyboardHeightObserver.java

/** * The observer that will be notified when the height of * the keyboard has changed */public interface KeyboardHeightObserver { /** * Called when the keyboard height has changed 0 means keyboard is closed * >= 1 means keyboard is opened. * * @param height The height of the keyboard in pixels * @param orientation The orientation either: Configuration.ORIENTATION_PORTRAIT or * Configuration.ORIENTATION_LANDSCAPE */ void onKeyboardHeightChanged(int height int orientation)}KeyboardHeightProvider.java

/** * The keyboard height provider this class uses a PopupWindow * to calculate the window height when the floating keyboard is opened and closed. */public class KeyboardHeightProvider extends PopupWindow { /** The tag for logging purposes */ private final static String TAG = "sample_KeyboardHeightProvider" /** The keyboard height observer */ private KeyboardHeightObserver observer /** The cached landscape height of the keyboard */ private int keyboardLandscapeHeight /** The cached portrait height of the keyboard */ private int keyboardPortraitHeight /** The view that is used to calculate the keyboard height */ private View popupView /** The parent view */ private View parentView /** The root activity that uses this KeyboardHeightProvider */ private Activity activity /** * Construct a new KeyboardHeightProvider * * @param activity The parent activity */ public KeyboardHeightProvider(Activity activity) { super(activity) this.activity = activity LayoutInflater inflator = (LayoutInflater) activity.getSystemService(Activity.LAYOUT_INFLATER_SERVICE) this.popupView = inflator.inflate(R.layout.keyboard_popup_window null false) setContentView(popupView) setSoftInputMode(LayoutParams.SOFT_INPUT_ADJUST_RESIZE | LayoutParams.SOFT_INPUT_STATE_ALWAYS_VISIBLE) setInputMethodMode(PopupWindow.INPUT_METHOD_NEEDED) parentView = activity.findViewById(android.R.id.content) setWidth(0) setHeight(LayoutParams.MATCH_PARENT) popupView.getViewTreeObserver().addOnGlobalLayoutListener(new OnGlobalLayoutListener() { @Override public void onGlobalLayout() { if (popupView != null) { handleOnGlobalLayout() } } }) } /** * Start the KeyboardHeightProvider this must be called after the onResume of the Activity. * PopupWindows are not allowed to be registered before the onResume has finished * of the Activity. */ public void start() { if (!isShowing() && parentView.getWindowToken() != null) { setBackgroundDrawable(new ColorDrawable(0)) showAtLocation(parentView Gravity.NO_GRAVITY 0 0) } } /** * Close the keyboard height provider * this provider will not be used anymore. */ public void close() { this.observer = null dismiss() } /** * Set the keyboard height observer to this provider. The * observer will be notified when the keyboard height has changed. * For example when the keyboard is opened or closed. * * @param observer The observer to be added to this provider. */ public void setKeyboardHeightObserver(KeyboardHeightObserver observer) { this.observer = observer } /** * Get the screen orientation * * @return the screen orientation */ private int getScreenOrientation() { return activity.getResources().getConfiguration().orientation } /** * Popup window itself is as big as the window of the Activity. * The keyboard can then be calculated by extracting the popup view bottom * from the activity window height. */ private void handleOnGlobalLayout() { Point screenSize = new Point() activity.getWindowManager().getDefaultDisplay().getSize(screenSize) Rect rect = new Rect() popupView.getWindowVisibleDisplayFrame(rect) // REMIND you may like to change this using the fullscreen size of the phone // and also using the status bar and navigation bar heights of the phone to calculate // the keyboard height. But this worked fine on a Nexus. int orientation = getScreenOrientation() int keyboardHeight = screenSize.y - rect.bottom if (keyboardHeight == 0) { notifyKeyboardHeightChanged(0 orientation) } else if (orientation == Configuration.ORIENTATION_PORTRAIT) { this.keyboardPortraitHeight = keyboardHeight notifyKeyboardHeightChanged(keyboardPortraitHeight orientation) } else { this.keyboardLandscapeHeight = keyboardHeight notifyKeyboardHeightChanged(keyboardLandscapeHeight orientation) } } private void notifyKeyboardHeightChanged(int height int orientation) { if (observer != null) { observer.onKeyboardHeightChanged(height orientation) } }}

使用方法

此处以在Activity中的使用进行举例。

实现接口

引入这两个类后,在当前Activity中实现接口KeyboardHeightObserver:

@Overridepublic void onKeyboardHeightChanged(int height int orientation) { String or = orientation == Configuration.ORIENTATION_PORTRAIT ? "portrait" : "landscape" Logger.d(TAG "onKeyboardHeightChanged in pixels: " + height + " " + or)}

定义并初始化

在当前Activity定义成员变量,并在onCreate()中进行初始化

private KeyboardHeightProvider mKeyboardHeightProvider@Overrideprotected void onCreate(@Nullable Bundle savedInstanceState) { ... mKeyboardHeightProvider = new KeyboardHeightProvider(this) new Handler().post(() -> mKeyboardHeightProvider.start())}

生命周期处理

初始化完成后,我们要在Activity中的生命周期中也要进行处理,以免内存泄露。

@Overrideprotected void onResume() { super.onResume() mKeyboardHeightProvider.setKeyboardHeightObserver(this)}@Overrideprotected void onPause() { super.onPause() mKeyboardHeightProvider.setKeyboardHeightObserver(null)}@Overrideprotected void onDestroy() { super.onDestroy() mKeyboardHeightProvider.close()}

总结

此时我们就可以正确获取的当前输入法的高度了,即使android:windowSoftInputMode="adjustNothing"时也可以正确获取到,这正是这个方法的强大之处,利用这个方法可以实现比如类似微信聊天的界面,流畅切换输入框,表情框等。

如有更多疑问,请参考我的其它Android相关博客:我的博客地址

文章评论

Top