Java tutorial
package fi.aalto.trafficsense.regularroutes.ui; import edu.mit.media.funf.util.IOUtil; import fi.aalto.trafficsense.regularroutes.ui.util.SystemUiHider; import android.annotation.TargetApi; import android.app.Activity; import android.content.pm.PackageManager; import android.content.res.Resources; import android.os.Build; import android.os.Bundle; import android.os.Handler; import android.view.MotionEvent; import android.view.View; import android.view.MenuItem; import android.support.v4.app.NavUtils; import android.widget.Button; import android.widget.TextView; import java.io.IOException; import java.io.InputStream; import fi.aalto.trafficsense.regularroutes.R; /** * Fullscreen about activity that hides other ui controls when screen is not touched inside * defined autohide delay. */ public class AboutActivity extends Activity { /** * Whether or not the system UI should be auto-hidden after * {@link #AUTO_HIDE_DELAY_MILLIS} milliseconds. */ private static final boolean AUTO_HIDE = true; /** * If {@link #AUTO_HIDE} is set, the number of milliseconds to wait after * user interaction before hiding the system UI. */ private static final int AUTO_HIDE_DELAY_MILLIS = 3000; /** * If set, will toggle the system UI visibility upon interaction. Otherwise, * will show the system UI visibility upon interaction. */ private static final boolean TOGGLE_ON_CLICK = true; /** * The flags to pass to {@link SystemUiHider#getInstance}. */ private static final int HIDER_FLAGS = SystemUiHider.FLAG_HIDE_NAVIGATION; /** * The instance of the {@link SystemUiHider} for this activity. */ private SystemUiHider mSystemUiHider; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_about); setupActionBar(); final View controlsView = findViewById(R.id.abt_Buttons); final View titleView = findViewById(R.id.abt_pageTitleField); final Button okButton = (Button) findViewById(R.id.abt_ok_button); // Set up an instance of SystemUiHider to control the system UI for // this activity. mSystemUiHider = SystemUiHider.getInstance(this, titleView, HIDER_FLAGS); mSystemUiHider.setup(); mSystemUiHider.setOnVisibilityChangeListener(new SystemUiHider.OnVisibilityChangeListener() { // Cached values. int mControlsHeight; int mShortAnimTime; @Override @TargetApi(Build.VERSION_CODES.HONEYCOMB_MR2) public void onVisibilityChange(boolean visible) { if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR2) { // If the ViewPropertyAnimator API is available // (Honeycomb MR2 and later), use it to animate the // in-layout UI controls at the bottom of the // screen. if (mControlsHeight == 0) { mControlsHeight = controlsView.getHeight(); } if (mShortAnimTime == 0) { mShortAnimTime = getResources().getInteger(android.R.integer.config_shortAnimTime); } controlsView.animate().translationY(visible ? 0 : mControlsHeight).setDuration(mShortAnimTime); } else { // If the ViewPropertyAnimator APIs aren't // available, simply show or hide the in-layout UI // controls. controlsView.setVisibility(visible ? View.VISIBLE : View.GONE); } if (visible && AUTO_HIDE) { // Schedule a hide(). delayedHide(AUTO_HIDE_DELAY_MILLIS); } } }); // Set up the user interaction to manually show or hide the system UI. titleView.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { if (TOGGLE_ON_CLICK) { mSystemUiHider.toggle(); } else { mSystemUiHider.show(); } } }); // Upon interacting with UI controls, delay any scheduled hide() // operations to prevent the jarring behavior of controls going away // while interacting with the UI. okButton.setOnTouchListener(mDelayHideTouchListener); okButton.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { // close finish(); } }); // Init fields initFields(); } @Override protected void onPostCreate(Bundle savedInstanceState) { super.onPostCreate(savedInstanceState); // Trigger the initial hide() shortly after the activity has been // created, to briefly hint to the user that UI controls // are available. delayedHide(100); } /** * Set up the {@link android.app.ActionBar}, if the API is available. */ @TargetApi(Build.VERSION_CODES.HONEYCOMB) private void setupActionBar() { if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) { // Show the Up button in the action bar. getActionBar().setDisplayHomeAsUpEnabled(true); } } @Override public boolean onOptionsItemSelected(MenuItem item) { int id = item.getItemId(); if (id == android.R.id.home) { // This ID represents the Home or Up button. In the case of this // activity, the Up button is shown. Use NavUtils to allow users // to navigate up one level in the application structure. For // more details, see the Navigation pattern on Android Design: // // http://developer.android.com/design/patterns/navigation.html#up-vs-back // // TODO: If Settings has multiple levels, Up should navigate up // that hierarchy. NavUtils.navigateUpFromSameTask(this); return true; } return super.onOptionsItemSelected(item); } /** * Touch listener to use for in-layout UI controls to delay hiding the * system UI. This is to prevent the jarring behavior of controls going away * while interacting with activity UI. */ View.OnTouchListener mDelayHideTouchListener = new View.OnTouchListener() { @Override public boolean onTouch(View view, MotionEvent motionEvent) { if (AUTO_HIDE) { delayedHide(AUTO_HIDE_DELAY_MILLIS); } return false; } }; Handler mHideHandler = new Handler(); Runnable mHideRunnable = new Runnable() { @Override public void run() { mSystemUiHider.hide(); } }; /** * Schedules a call to hide() in [delay] milliseconds, canceling any * previously scheduled calls. */ private void delayedHide(int delayMillis) { mHideHandler.removeCallbacks(mHideRunnable); mHideHandler.postDelayed(mHideRunnable, delayMillis); } private void initFields() { final TextView clientVersionField = (TextView) findViewById(R.id.abt_clientVersionField); try { final String ver = getPackageManager().getPackageInfo(this.getPackageName(), 0).versionName; clientVersionField.setText(ver); } catch (PackageManager.NameNotFoundException e) { clientVersionField.setText("<unknown>"); } loadLicenseInfo(); loadContributions(); } private void loadContributions() { TextView contributionsField = (TextView) findViewById(R.id.abt_contributions); loadAndFillField(R.raw.contributions, contributionsField); } private void loadLicenseInfo() { TextView legalNoticesField = (TextView) findViewById(R.id.abt_legalNotice); loadAndFillField(R.raw.legal_notice, legalNoticesField); } private void loadAndFillField(int resId, TextView field) { Resources res = getResources(); if (res == null || field == null) return; try { InputStream stream = res.openRawResource(resId); final String fileContent = IOUtil.inputStreamToString(stream, "utf-8"); field.setText(fileContent); } catch (IOException e) { field.setText("<load failed>"); } } }