Android APP适配全面屏手机的技术要点

<meta-data android:name="android.max_aspect"  android:value="ratio_float"/>

<meta-data android:name="android.max_aspect" android:value="2.1" />

public void setMaxAspect() {
        ApplicationInfo applicationInfo = null;
        try {
            applicationInfo = getPackageManager().getApplicationInfo(getPackageName(), PackageManager.GET_META_DATA);
        } catch (PackageManager.NameNotFoundException e) {
            e.printStackTrace();
        }
        if(applicationInfo == null){
            throw new IllegalArgumentException(" get application info = null, has no meta data! ");
        }
        applicationInfo.metaData.putString("android.max_aspect", "2.1");
    }

compile 'com.android.support:percent:23.0.1'

@Override
public boolean hasNavigationBar() {
    return mPolicy.hasNavigationBar();
}

// Use this instead of checking config_showNavigationBar so that it can be consistently
// overridden by qemu.hw.mainkeys in the emulator.
@Override
public boolean hasNavigationBar() {
    return mHasNavigationBar;
}

public void setInitialDisplaySize(Display display, int width, int height, int density) {
        ...
        ...
        mHasNavigationBar = res.getBoolean(com.android.internal.R.bool.config_showNavigationBar);

        // Allow a system property to override this. Used by the emulator.
        // See also hasNavigationBar().
        String navBarOverride = SystemProperties.get("qemu.hw.mainkeys");
        if ("1".equals(navBarOverride)) {
            mHasNavigationBar = false;
        } else if ("0".equals(navBarOverride)) {
            mHasNavigationBar = true;
        }
        ...
        ...
}

<!-- Whether a software navigation bar should be shown. NOTE: in the future this may be  
     autodetected from the Configuration. -->  
<bool name="config_showNavigationBar">false</bool>

//判断是否存在NavigationBar
public static boolean hasNavigationBar(Context context) {
    boolean hasNavigationBar = false;
    Resources rs = context.getResources();
    int id = rs.getIdentifier("config_showNavigationBar", "bool", "android");
    if (id > 0) {
        hasNavigationBar = rs.getBoolean(id);
    }
    try {
        //反射获取SystemProperties类，并调用它的get方法
        Class systemPropertiesClass = Class.forName("android.os.SystemProperties");
        Method m = systemPropertiesClass.getMethod("get", String.class);
        String navBarOverride = (String) m.invoke(systemPropertiesClass, "qemu.hw.mainkeys");
        if ("1".equals(navBarOverride)) {
            hasNavigationBar = false;
        } else if ("0".equals(navBarOverride)) {
            hasNavigationBar = true;
        }
    } catch (Exception e) {
        e.printStackTrace();
    }
    return hasNavigationBar;
}

public static IWindowManager getWindowManagerService() {
    synchronized (WindowManagerGlobal.class) {
        if (sWindowManagerService == null) {
            sWindowManagerService = IWindowManager.Stub.asInterface(
                    ServiceManager.getService("window"));
            try {
                if (sWindowManagerService != null) {
                    ValueAnimator.setDurationScale(
                            sWindowManagerService.getCurrentAnimatorScale());
                }
            } catch (RemoteException e) {
                throw e.rethrowFromSystemServer();
            }
        }
        return sWindowManagerService;
    }
}

/**
 * 判断设备是否存在NavigationBar
 *
 * @return true 存在, false 不存在
 */
public static boolean deviceHasNavigationBar() {
    boolean haveNav = false;
    try {
        //1.通过WindowManagerGlobal获取windowManagerService
        // 反射方法：IWindowManager windowManagerService = WindowManagerGlobal.getWindowManagerService();
        Class<?> windowManagerGlobalClass = Class.forName("android.view.WindowManagerGlobal");
        Method getWmServiceMethod = windowManagerGlobalClass.getDeclaredMethod("getWindowManagerService");
        getWmServiceMethod.setAccessible(true);
        //getWindowManagerService是静态方法，所以invoke null
        Object iWindowManager = getWmServiceMethod.invoke(null);  

        //2.获取windowMangerService的hasNavigationBar方法返回值
        // 反射方法：haveNav = windowManagerService.hasNavigationBar();
        Class<?> iWindowManagerClass = iWindowManager.getClass();
        Method hasNavBarMethod = iWindowManagerClass.getDeclaredMethod("hasNavigationBar");
        hasNavBarMethod.setAccessible(true);
        haveNav = (Boolean) hasNavBarMethod.invoke(iWindowManager);
    } catch (Exception e) {
        e.printStackTrace();
    }
    return haveNav;
}

private static final String NAVIGATION_GESTURE = "navigation_gesture_on";
private static final int NAVIGATION_GESTURE_OFF = 0;

/**
 * 获取vivo手机设置中的"navigation_gesture_on"值，判断当前系统是使用导航键还是手势导航操作
 * @param context app Context
 * @return false 表示使用的是虚拟导航键(NavigationBar)， true 表示使用的是手势， 默认是false
 */
public static boolean vivoNavigationGestureEnabled(Context context) {
    int val = Settings.Secure.getInt(context.getContentResolver(), NAVIGATION_GESTURE, NAVIGATION_GESTURE_OFF);
    return val != NAVIGATION_GESTURE_OFF;
}

//vivoNavigationGestureEnabled()从设置中取不到值的话，返回false，因此也不会影响在其他手机上的判断
boolean hasNavigationBar = hasNavigationBar(this) && !vivoNavigationGestureEnabled(this);

View decorView = getWindow().getDecorView();
// Hide both the navigation bar and the status bar.
// SYSTEM_UI_FLAG_FULLSCREEN is only available on Android 4.1 and higher, but as
// a general rule, you should design your app to hide the status bar whenever you
// hide the navigation bar.
int uiOptions = View.SYSTEM_UI_FLAG_HIDE_NAVIGATION | View.SYSTEM_UI_FLAG_FULLSCREEN;
decorView.setSystemUiVisibility(uiOptions);

public void showBar(){  
    int uiOptions = getWindow().getDecorView().getSystemUiVisibility();  
    int newUiOptions = uiOptions;  
    boolean isImmersiveModeEnabled =  
            ((uiOptions | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY) == uiOptions);  
    if (isImmersiveModeEnabled) {  
        Log.i(TAG, "Turning immersive mode mode off. ");  
        //先取 非 后再 与， 把对应位置的1 置成0，原本为0的还是0  
        if (Build.VERSION.SDK_INT >= 14) {  
            newUiOptions &= ~View.SYSTEM_UI_FLAG_HIDE_NAVIGATION;  
        }
        if (Build.VERSION.SDK_INT >= 16) {  
            newUiOptions &= ~View.SYSTEM_UI_FLAG_FULLSCREEN;  
        }
        if (Build.VERSION.SDK_INT >= 18) {  
            newUiOptions &= ~View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY;  
        }  
        getWindow().getDecorView().setSystemUiVisibility(newUiOptions);  
    }  
}  
  
  
public void hideBar() {  
    // The UI options currently enabled are represented by a bitfield.  
    // getSystemUiVisibility() gives us that bitfield.  
    int uiOptions = getWindow().getDecorView().getSystemUiVisibility();  
    int newUiOptions = uiOptions;  
    boolean isImmersiveModeEnabled =  
            ((uiOptions | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY) == uiOptions);  
    if (!isImmersiveModeEnabled) {  
        Log.i(TAG, "Turning immersive mode mode on. ");  
        if (Build.VERSION.SDK_INT >= 14) {  
            newUiOptions |= View.SYSTEM_UI_FLAG_HIDE_NAVIGATION;  
        }
        if (Build.VERSION.SDK_INT >= 16) {  
            newUiOptions |= View.SYSTEM_UI_FLAG_FULLSCREEN;  
        }  
        if (Build.VERSION.SDK_INT >= 18) {  
            newUiOptions |= View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY;  
        }
        getWindow().getDecorView().setSystemUiVisibility(newUiOptions);  
    }  
}

/** 
 * Detects and toggles immersive mode (also known as "hidey bar" mode). 
 */  
public void toggleHideyBar() {  
  
    // BEGIN_INCLUDE (get_current_ui_flags)  
    // The UI options currently enabled are represented by a bitfield.  
    // getSystemUiVisibility() gives us that bitfield.  
    int uiOptions = getActivity().getWindow().getDecorView().getSystemUiVisibility();  
    int newUiOptions = uiOptions;  
    // END_INCLUDE (get_current_ui_flags)  
    // BEGIN_INCLUDE (toggle_ui_flags)  
    boolean isImmersiveModeEnabled =  
            ((uiOptions | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY) == uiOptions);  
    if (isImmersiveModeEnabled) {  
        Log.i(TAG, "Turning immersive mode mode off. ");  
    } else {  
        Log.i(TAG, "Turning immersive mode mode on.");  
    }  
  
    // Navigation bar hiding:  Backwards compatible to ICS.  
    if (Build.VERSION.SDK_INT >= 14) {  
        newUiOptions ^= View.SYSTEM_UI_FLAG_HIDE_NAVIGATION;  
    }  
  
    // Status bar hiding: Backwards compatible to Jellybean  
    if (Build.VERSION.SDK_INT >= 16) {  
        newUiOptions ^= View.SYSTEM_UI_FLAG_FULLSCREEN;  
    }  
  
    // Immersive mode: Backward compatible to KitKat.  
    // Note that this flag doesn't do anything by itself, it only augments the behavior  
    // of HIDE_NAVIGATION and FLAG_FULLSCREEN.  For the purposes of this sample  
    // all three flags are being toggled together.  
    // Note that there are two immersive mode UI flags, one of which is referred to as "sticky".  
    // Sticky immersive mode differs in that it makes the navigation and status bars  
    // semi-transparent, and the UI flag does not get cleared when the user interacts with  
    // the screen.  
    if (Build.VERSION.SDK_INT >= 18) {  
        newUiOptions ^= View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY;  
    }  
  
    getActivity().getWindow().getDecorView().setSystemUiVisibility(newUiOptions);  
    //END_INCLUDE (set_ui_flags)  
}