福州做网站建设服务商,建设淘宝客网站,淘宝搜索关键词排名,中国建设门户网登录我是Android开发世界的新手,我已经建立了一个简单的“Hello World”应用程序.首先,活动请求一个文本.当单击“Go”按钮时,应用程序将启动显示输入文本的第二个活动.如果我单击HOME按钮,然后单击应用程序图标,该应用程序将再次启动第一个活动,但是如果我按住主屏幕按钮并单击“最…我是Android开发世界的新手,我已经建立了一个简单的“Hello World”应用程序.首先,活动请求一个文本.当单击“Go”按钮时,应用程序将启动显示输入文本的第二个活动.如果我单击HOME按钮,然后单击应用程序图标,该应用程序将再次启动第一个活动,但是如果我按住主屏幕按钮并单击“最近的应用程序”栏中的图标,它会恢复我离开的应用程序.如何避免这种情况即使点击启动器图标,我也需要我的应用程序恢复.MainActivity.java,package com.example.myfirstandroidapp;import android.app.Activity;import android.content.Intent;import android.os.Bundle;import android.view.Menu;import android.view.View;import android.widget.EditText;public class MainActivity extends Activity {public final static String EXTRA_MESSAGE com.example.myfirstapp.MESSAGE;Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);}Overridepublic boolean onCreateOptionsMenu(Menu menu) {// Inflate the menu; this adds items to the action bar if it is present.getMenuInflater().inflate(R.menu.main,menu);return true;}/** Called when the user clicks the Send button */public void sendMessage(View view){// Do something in response to buttonIntent intent new Intent(this,DisplayMessageActivity.class);EditText editText (EditText) findViewById(R.id.txtName);String message editText.getText().toString();intent.putExtra(EXTRA_MESSAGE,message);startActivity(intent);}}DisplayActivity.java,package com.example.myfirstandroidapp;import android.annotation.TargetApi;import android.app.Activity;import android.content.Intent;import android.os.Build;import android.os.Bundle;import android.support.v4.app.NavUtils;import android.view.Menu;import android.view.MenuItem;import android.widget.TextView;public class DisplayMessageActivity extends Activity {Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);// Get the message from the intentIntent intent getIntent();String message intent.getStringExtra(MainActivity.EXTRA_MESSAGE);// Create the text viewTextView textView new TextView(this);textView.setTextSize(40);textView.setText(message);// Set the text view as the activity layoutsetContentView(textView);// Show the Up button in the action bar.setupActionBar();}/*** 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) {getActionBar().setDisplayHomeAsUpEnabled(true);}}Overridepublic boolean onCreateOptionsMenu(Menu menu) {// Inflate the menu; this adds items to the action bar if it is present.getMenuInflater().inflate(R.menu.display_message,menu);return true;}Overridepublic void onDestroy(){super.onDestroy();}Overridepublic boolean onOptionsItemSelected(MenuItem item) {switch (item.getItemId()) {case 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//NavUtils.navigateUpFromSaMetask(this);return true;}return super.onOptionsItemSelected(item);}}activity_main.xml中,xmlns:toolshttp://schemas.android.com/toolsandroid:layout_widthmatch_parentandroid:layout_heightmatch_parentandroid:paddingBottomdimen/activity_vertical_marginandroid:paddingLeftdimen/activity_horizontal_marginandroid:paddingRightdimen/activity_horizontal_marginandroid:paddingTopdimen/activity_vertical_margintools:context.MainActivity android:idid/txtNameandroid:layout_widthwrap_contentandroid:layout_heightwrap_contentandroid:layout_marginTop70dpandroid:ems10 android:idid/btnGoandroid:layout_widthwrap_contentandroid:layout_heightwrap_contentandroid:layout_alignBottomid/txtNameandroid:layout_alignParentRighttrueandroid:onClicksendMessageandroid:textGo! /android:idid/textView1android:layout_widthwrap_contentandroid:layout_heightwrap_contentandroid:layout_alignLeftid/txtNameandroid:layout_alignParentToptrueandroid:layout_marginTop18dpandroid:textPlease input your name:android:textAppearance?android:attr/textAppearanceMedium /activity_display_message.xml,xmlns:toolshttp://schemas.android.com/toolsandroid:layout_widthmatch_parentandroid:layout_heightmatch_parentandroid:paddingBottomdimen/activity_vertical_marginandroid:paddingLeftdimen/activity_horizontal_marginandroid:paddingRightdimen/activity_horizontal_marginandroid:paddingTopdimen/activity_vertical_margintools:context.DisplayMessageActivity android:idid/textView2android:layout_widthwrap_contentandroid:layout_heightwrap_contentandroid:textstring/hello_world /AndroidManifest.xml中,packagecom.example.myfirstandroidappandroid:versionCode1android:versionName1.0 android:minSdkVersion9android:targetSdkVersion10 /android:allowBackuptrueandroid:icondrawable/ic_launcherandroid:labelstring/app_nameandroid:themestyle/AppTheme android:namecom.example.myfirstandroidapp.MainActivityandroid:labelstring/app_name android:namecom.example.myfirstandroidapp.DisplayMessageActivityandroid:labelstring/title_activity_display_messageandroid:parentActivityNamecom.example.myfirstandroidapp.MainActivity android:nameandroid.support.PARENT_ACTIVITYandroid:valuecom.example.myfirstandroidapp.MainActivity /
