Java tutorial
/* * Copyright (C) 2011 University of Washington * * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except * in compliance with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software distributed under the License * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express * or implied. See the License for the specific language governing permissions and limitations under * the License. */ package org.odk.collect.android.activities; import android.Manifest; import android.app.Activity; import android.app.AlertDialog; import android.content.DialogInterface; import android.content.Intent; import android.content.SharedPreferences; import android.content.SharedPreferences.Editor; import android.content.pm.PackageInfo; import android.content.pm.PackageManager; import android.content.pm.PackageManager.NameNotFoundException; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.os.Bundle; import android.preference.PreferenceManager; import android.support.v4.app.ActivityCompat; import android.support.v4.content.ContextCompat; import android.view.View; import android.view.Window; import android.widget.ImageView; import android.widget.LinearLayout; import org.odk.collect.android.R; import org.odk.collect.android.application.Collect; import org.odk.collect.android.preferences.PreferencesActivity; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; public class SplashScreenActivity extends Activity { private static final int mSplashTimeout = 2000; // milliseconds private static final boolean EXIT = true; private static final int MY_PERMISSIONS_WRITE_STORAGE = 1; private int mImageMaxWidth; private AlertDialog mAlertDialog; @Override public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) { if (requestCode == MY_PERMISSIONS_WRITE_STORAGE) { if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) { Collect.createODKDirs(); } else { ActivityCompat.requestPermissions(this, new String[] { Manifest.permission.WRITE_EXTERNAL_STORAGE }, MY_PERMISSIONS_WRITE_STORAGE); } } else { super.onRequestPermissionsResult(requestCode, permissions, grantResults); } } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); if (ContextCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) { ActivityCompat.requestPermissions(this, new String[] { Manifest.permission.WRITE_EXTERNAL_STORAGE }, MY_PERMISSIONS_WRITE_STORAGE); } else { // must be at the beginning of any activity that can be called from an external intent try { Collect.createODKDirs(); } catch (RuntimeException e) { createErrorDialog(e.getMessage(), EXIT); return; } } mImageMaxWidth = getWindowManager().getDefaultDisplay().getWidth(); // this splash screen should be a blank slate requestWindowFeature(Window.FEATURE_NO_TITLE); setContentView(R.layout.splash_screen); // get the shared preferences object SharedPreferences mSharedPreferences = PreferenceManager.getDefaultSharedPreferences(this); Editor editor = mSharedPreferences.edit(); // get the package info object with version number PackageInfo packageInfo = null; try { packageInfo = getPackageManager().getPackageInfo(getPackageName(), PackageManager.GET_META_DATA); } catch (NameNotFoundException e) { e.printStackTrace(); } boolean firstRun = mSharedPreferences.getBoolean(PreferencesActivity.KEY_FIRST_RUN, true); boolean showSplash = mSharedPreferences.getBoolean(PreferencesActivity.KEY_SHOW_SPLASH, false); String splashPath = mSharedPreferences.getString(PreferencesActivity.KEY_SPLASH_PATH, getString(R.string.default_splash_path)); // if you've increased version code, then update the version number and set firstRun to true if (mSharedPreferences.getLong(PreferencesActivity.KEY_LAST_VERSION, 0) < packageInfo.versionCode) { editor.putLong(PreferencesActivity.KEY_LAST_VERSION, packageInfo.versionCode); editor.commit(); firstRun = true; } // do all the first run things if (firstRun || showSplash) { editor.putBoolean(PreferencesActivity.KEY_FIRST_RUN, false); editor.commit(); startSplashScreen(splashPath); } else { endSplashScreen(); } } private void endSplashScreen() { // launch new activity and close splash screen startActivity(new Intent(SplashScreenActivity.this, MainMenuActivity.class)); finish(); } // decodes image and scales it to reduce memory consumption private Bitmap decodeFile(File f) { Bitmap b = null; try { // Decode image size BitmapFactory.Options o = new BitmapFactory.Options(); o.inJustDecodeBounds = true; FileInputStream fis = new FileInputStream(f); BitmapFactory.decodeStream(fis, null, o); try { fis.close(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } int scale = 1; if (o.outHeight > mImageMaxWidth || o.outWidth > mImageMaxWidth) { scale = (int) Math.pow(2, (int) Math.round( Math.log(mImageMaxWidth / (double) Math.max(o.outHeight, o.outWidth)) / Math.log(0.5))); } // Decode with inSampleSize BitmapFactory.Options o2 = new BitmapFactory.Options(); o2.inSampleSize = scale; fis = new FileInputStream(f); b = BitmapFactory.decodeStream(fis, null, o2); try { fis.close(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } catch (FileNotFoundException e) { } return b; } private void startSplashScreen(String path) { // add items to the splash screen here. makes things less distracting. ImageView iv = (ImageView) findViewById(R.id.splash); LinearLayout ll = (LinearLayout) findViewById(R.id.splash_default); File f = new File(path); if (f.exists()) { iv.setImageBitmap(decodeFile(f)); ll.setVisibility(View.GONE); iv.setVisibility(View.VISIBLE); } // create a thread that counts up to the timeout Thread t = new Thread() { int count = 0; @Override public void run() { try { super.run(); while (count < mSplashTimeout) { sleep(100); count += 100; } } catch (Exception e) { e.printStackTrace(); } finally { endSplashScreen(); } } }; t.start(); } private void createErrorDialog(String errorMsg, final boolean shouldExit) { Collect.getInstance().getActivityLogger().logAction(this, "createErrorDialog", "show"); mAlertDialog = new AlertDialog.Builder(this).create(); mAlertDialog.setIcon(android.R.drawable.ic_dialog_info); mAlertDialog.setMessage(errorMsg); DialogInterface.OnClickListener errorListener = new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int i) { switch (i) { case DialogInterface.BUTTON_POSITIVE: Collect.getInstance().getActivityLogger().logAction(this, "createErrorDialog", "OK"); if (shouldExit) { finish(); } break; } } }; mAlertDialog.setCancelable(false); mAlertDialog.setButton(getString(R.string.ok), errorListener); mAlertDialog.show(); } @Override protected void onStart() { super.onStart(); Collect.getInstance().getActivityLogger().logOnStart(this); } @Override protected void onStop() { Collect.getInstance().getActivityLogger().logOnStop(this); super.onStop(); } }