Android知识笔记：Android 仿iOS 侧滑关闭Activity框架透底问题

    <style name="AppBaseTheme" parent="@style/Theme.AppCompat.Light.NoActionBar">
        <item name="android:windowIsTranslucent">false</item>
        <item name="android:windowBackground">@color/transparent</item>
    </style>

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        if (current_theme!= -1){
            this.setTheme(current_theme);
        }
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        findViewById(R.id.bt_theme).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                changeTheme(GREEN_THEME);
            }
        });
    }

    public void changeTheme(int index) {
        switch (index) {
            case DEFAULT_THEME:
                current_theme = R.style.DefaultTheme;
                break;
            case GREEN_THEME:
                current_theme = R.style.GreenTheme;
                break;
            case ORANGE_THEME:
                current_theme = R.style.OrangeTheme;
                break;
            default:
                break;
        }
    }

    protected void reload() {
        Intent intent = getIntent();
        overridePendingTransition(0, 0);
        intent.addFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);
        finish();
        overridePendingTransition(0, 0);
        startActivity(intent);
    }

     /**
     * Convert a translucent themed Activity {@link android.R.attr#windowIsTranslucent} back from
     * opaque to translucent following a call to {@link #convertFromTranslucent()}.
     * <p>
     * Calling this allows the Activity behind this one to be seen again. Once all such Activities
     * have been redrawn {@link TranslucentConversionListener#onTranslucentConversionComplete} will
     * be called indicating that it is safe to make this activity translucent again. Until
     * {@link TranslucentConversionListener#onTranslucentConversionComplete} is called the image
     * behind the frontmost Activity will be indeterminate.
     * <p>
     * This call has no effect on non-translucent activities or on activities with the
     * {@link android.R.attr#windowIsFloating} attribute.
     *
     * @param callback the method to call when all visible Activities behind this one have been
     * drawn and it is safe to make this Activity translucent again.
     * @param options activity options delivered to the activity below this one. The options
     * are retrieved using {@link #getActivityOptions}.
     * @return <code>true</code> if Window was opaque and will become translucent or
     * <code>false</code> if window was translucent and no change needed to be made.
     *
     * @see #convertFromTranslucent()
     * @see TranslucentConversionListener
     *
     * @hide
     */
    @SystemApi
    public boolean convertToTranslucent(TranslucentConversionListener callback,
            ActivityOptions options) {
        boolean drawComplete;
        try {
            mTranslucentCallback = callback;
            mChangeCanvasToTranslucent = ActivityManager.getService().convertToTranslucent(
                    mToken, options == null ? null : options.toBundle());
            WindowManagerGlobal.getInstance().changeCanvasOpacity(mToken, false);
            drawComplete = true;
        } catch (RemoteException e) {
            // Make callback return as though it timed out.
            mChangeCanvasToTranslucent = false;
            drawComplete = false;
        }
        if (!mChangeCanvasToTranslucent && mTranslucentCallback != null) {
            // Window is already translucent.
            mTranslucentCallback.onTranslucentConversionComplete(drawComplete);
        }
        return mChangeCanvasToTranslucent;
    }

 /**
     * Convert a translucent themed Activity {@link android.R.attr#windowIsTranslucent} to a
     * fullscreen opaque Activity.
     * <p>
     * Call this whenever the background of a translucent Activity has changed to become opaque.
     * Doing so will allow the {@link android.view.Surface} of the Activity behind to be released.
     * <p>
     * This call has no effect on non-translucent activities or on activities with the
     * {@link android.R.attr#windowIsFloating} attribute.
     *
     * @see #convertToTranslucent(android.app.Activity.TranslucentConversionListener,
     * ActivityOptions)
     * @see TranslucentConversionListener
     *
     * @hide
     */
    @SystemApi
    public void convertFromTranslucent() {
        try {
            mTranslucentCallback = null;
            if (ActivityManager.getService().convertFromTranslucent(mToken)) {
                WindowManagerGlobal.getInstance().changeCanvasOpacity(mToken, true);
            }
        } catch (RemoteException e) {
            // pass
        }
    }

    /**
     * Convert a translucent themed Activity
     * 将Activity 改为透明
     */
    public static void convertActivityToTranslucent(Activity activity) {
        long timeMillis = SystemClock.currentThreadTimeMillis();
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
            convertActivityToTranslucentAfterL(activity);
        } else {
            convertActivityToTranslucentBeforeL(activity);
        }
        FxLog.d("convertActivity :  convertActivityToTranslucent  time = " + (SystemClock.currentThreadTimeMillis() - timeMillis));
    }

    /**
     * Calling the convertToTranslucent method on platforms before Android 5.0
     */
    public static void convertActivityToTranslucentBeforeL(Activity activity) {
        try {
            Class<?>[] classes = Activity.class.getDeclaredClasses();
            Class<?> translucentConversionListenerClazz = null;
            for (Class clazz : classes) {
                if (clazz.getSimpleName().contains("TranslucentConversionListener")) {
                    translucentConversionListenerClazz = clazz;
                }
            }
            Method method = Activity.class.getDeclaredMethod("convertToTranslucent",
                    translucentConversionListenerClazz);
            method.setAccessible(true);
            method.invoke(activity, new Object[] {
                    null
            });
        } catch (Throwable t) {
        }
    }

    /**
     * Calling the convertToTranslucent method on platforms after Android 5.0
     */
    private static void convertActivityToTranslucentAfterL(Activity activity) {
        try {
            Method getActivityOptions = Activity.class.getDeclaredMethod("getActivityOptions");
            getActivityOptions.setAccessible(true);
            Object options = getActivityOptions.invoke(activity);

            Class<?>[] classes = Activity.class.getDeclaredClasses();
            Class<?> translucentConversionListenerClazz = null;
            for (Class clazz : classes) {
                if (clazz.getSimpleName().contains("TranslucentConversionListener")) {
                    translucentConversionListenerClazz = clazz;
                }
            }
            Method convertToTranslucent = Activity.class.getDeclaredMethod("convertToTranslucent",
                    translucentConversionListenerClazz, ActivityOptions.class);
            convertToTranslucent.setAccessible(true);
            convertToTranslucent.invoke(activity, null, options);
        } catch (Throwable t) {
        }
    }

    public void setWindowToTranslucent(boolean translucent) {
        if (isTranslucentWindow == translucent || !isSlidingEnabled()){
            return;
        }
        isTranslucentWindow = translucent;
        if (isTranslucentWindow) {
            convertActivityToTranslucent(((Activity) getContext()));
        } else {
            convertActivityFromTranslucent(((Activity) getContext()));
        }
    }