アプリケーションの最上位ビューを取得する糞Tipsアプリ

RootViewsActivity.java

package com.esperia09.android.test_android.reflection;

import java.lang.reflect.Field;

import android.app.AlertDialog;
import android.app.AlertDialog.Builder;
import android.app.Dialog;
import android.graphics.Color;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v4.app.DialogFragment;
import android.support.v4.app.FragmentActivity;
import android.text.TextUtils;
import android.util.Log;
import android.view.Gravity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.WindowManager;
import android.view.WindowManager.LayoutParams;
import android.widget.TextView;
import android.widget.Toast;

public class RootViewsActivity extends FragmentActivity {
    private static final String TAG = RootViewsActivity.class.getSimpleName();
    private static final String MENU_ADD_TEXT = "TextView追加";
    private static final String MENU_SHOW_DIALOG = "ダイアログ表示";
    private static final String MENU_SHOW_TOAST = "トースト表示";

    private WindowWatchTask mTask;
    private TextView mTextView;
    private TextView mWindowTextView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        mTextView = new TextView(this);
        setContentView(mTextView);
    }

    @Override
    protected void onResume() {
        super.onResume();

        mTask = new WindowWatchTask() {
            @Override
            protected void onProgressUpdate(Void... values) {
                View[] views = getViews(getWindowManager());
                if (views != null) {
                    StringBuilder sb = new StringBuilder();
                    sb.append("count=").append(views.length).append("\n");
                    for (View v : views) {
                        sb.append(v).append("\n");
                    }
                    mTextView.setText(sb.toString());
                }
            }
        };
        mTask.execute();
    }

    @Override
    protected void onPause() {
        super.onPause();

        mTask.cancel(false);
        mTask = null;
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        menu.add(MENU_ADD_TEXT);
        menu.add(MENU_SHOW_DIALOG);
        menu.add(MENU_SHOW_TOAST);
        return super.onCreateOptionsMenu(menu);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        CharSequence title = item.getTitle();
        if (TextUtils.equals(MENU_ADD_TEXT, title)) {
            // TextViewを追加
            WindowManager wm = getWindowManager();

            if (mWindowTextView != null) {
                wm.removeView(mWindowTextView);
            }
            mWindowTextView = new TextView(this);
            mWindowTextView.setBackgroundColor(Color.WHITE);
            mWindowTextView.setText("むおおおお");
            mWindowTextView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    WindowManager wm = getWindowManager();
                    wm.removeView(mWindowTextView);
                    mWindowTextView = null;
                }
            });
            LayoutParams params = createParams();
            wm.addView(mWindowTextView, params);
        } else if (TextUtils.equals(MENU_SHOW_DIALOG, title)) {
            // ダイアログ表示
            new DialogFragment() {
                @Override
                public Dialog onCreateDialog(Bundle savedInstanceState) {
                    Builder builder = new AlertDialog.Builder(getActivity());
                    builder.setMessage("ダイアログ");
                    builder.setPositiveButton("ok", null);

                    return builder.create();
                }
            }.show(getSupportFragmentManager(), "MyDialog");
        } else if (TextUtils.equals(MENU_SHOW_TOAST, title)) {
            Toast.makeText(this, "トースト表示", Toast.LENGTH_LONG).show();
        }
        return super.onOptionsItemSelected(item);
    }

    /**
     * WindowManagerのビューのリストを取得する
     */
    private View[] getViews(WindowManager wm) {
        try {
            Field declaredField = wm.getClass().getDeclaredField("mGlobal");
            declaredField.setAccessible(true);
            Object windowManagerGlobalInstance = declaredField.get(wm);

            Field viewsField = windowManagerGlobalInstance.getClass().getDeclaredField("mViews");
            viewsField.setAccessible(true);
            Object object = viewsField.get(windowManagerGlobalInstance);

            View[] views = View[].class.cast(object);

            return views;
        } catch (Exception e) {
            Log.e(TAG, "メソッド呼び出しに失敗", e);
        }

        return null;
    }

    private LayoutParams createParams() {
        LayoutParams params = new WindowManager.LayoutParams();
        params.width = WindowManager.LayoutParams.WRAP_CONTENT;
        params.height = WindowManager.LayoutParams.WRAP_CONTENT;
        params.gravity = Gravity.LEFT | Gravity.TOP;
        return params;
    }

    private static class WindowWatchTask extends AsyncTask<Void, Void, Void> {
        private static final int TIME_DST = 500; // ms

        @Override
        protected Void doInBackground(Void... params) {
            while (!isCancelled()) {
                publishProgress();
                try {
                    Thread.sleep(TIME_DST);
                } catch (InterruptedException e) {
                    cancel(false);
                }
            }
            return null;
        }

    }
}