Java 单击按钮时无法启动其他活动
我的项目非常简单,仅用于培训目的。当我单击主布局上的按钮时,我正试图加载另一个界面/视图/活动。以下是主要活动的代码:Java 单击按钮时无法启动其他活动,java,android,Java,Android,我的项目非常简单,仅用于培训目的。当我单击主布局上的按钮时,我正试图加载另一个界面/视图/活动。以下是主要活动的代码: package com.example.interfacemanipulation; import android.app.Activity; import android.content.Intent; import android.os.Bundle; import android.view.Menu; import android.widget.TextView; p
package com.example.interfacemanipulation;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.widget.TextView;
public class WelcomeActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Intent intent = getIntent();
String message = intent.getStringExtra(MainActivity.EXTRA_MESSAGE);
TextView textView = new TextView(this);
textView.setTextSize(40);
textView.setText(message);
// Set the text view as the activity layout
setContentView(textView);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.welcome, menu);
return true;
}
}
包com.example.interfacemanipulation
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 static final String EXTRA_MESSAGE = "Something Here....";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
@Override
public 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;
}
public void goToWelcomeActivityMethod(View view)
{
Intent intent = new Intent(this, WelcomeActivity.class);
EditText editText = (EditText) findViewById(R.id.welcomeMessage);
String message = editText.getText().toString();
intent.putExtra(EXTRA_MESSAGE, message);
startActivity(intent);
}
}
这是其他活动中的代码:
package com.example.interfacemanipulation;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.widget.TextView;
public class WelcomeActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Intent intent = getIntent();
String message = intent.getStringExtra(MainActivity.EXTRA_MESSAGE);
TextView textView = new TextView(this);
textView.setTextSize(40);
textView.setText(message);
// Set the text view as the activity layout
setContentView(textView);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.welcome, menu);
return true;
}
}
这里的代码基本上是根据Google文档修改的。我只想能够加载第二个活动的视图,其中包含标签。这是我的舱单:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.interfacemanipulation"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="17" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.example.interfacemanipulation.MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="com.example.interfacemanipulation.WelcomeActivity"
android:label="@string/title_activity_welcome" >
</activity>
</application>
</manifest>
在过去的4天里,我一直在尝试android…因此我感谢您的支持在主活动的布局XML中,在按钮声明中添加属性
android:onClick=“goToWelcomeActivityMethod”
。
这样,按下按钮时将调用方法goToWelcomeActivityMethod
对于“其他”方式,请检查您有两个问题:1。你没有带你去活动的按钮(或者至少你没有在你发布的代码中显示它。如果你有,那么你没有为该按钮设置
onClickListener
)。2.您不会调用将您带到第二个活动的方法
要有一个按钮将您带到另一个活动,您需要将该按钮添加到布局中,然后添加onClickListener
,当您单击它时,它将执行您的goToWelcomeActivityMethod
,如下所示:
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 static final String EXTRA_MESSAGE = "Something Here....";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//this will insert the button into the Main Activity layout
Button goToWelcome = (Button)findViewById(R.id.goToWelcome);
//this is the onClickListener which will call the method to go to the next activity
goToWelcome.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
goToWelcomeActivityMethod();
}
});
}
@Override
public 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;
}
//you don't need to pass in the View
public void goToWelcomeActivityMethod()
{
Intent intent = new Intent(this, WelcomeActivity.class);
EditText editText = (EditText) findViewById(R.id.welcomeMessage);
String message = editText.getText().toString();
intent.putExtra(EXTRA_MESSAGE, message);
startActivity(intent);
}
}
然后在XML文件中,确保也添加了按钮:
<Button
android:id="@+id/goToWelcome"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:text="Go To Welcome" />
我看不出您在哪里调用
goToWelcomeActivityMethod
。。。或者这就是您遇到的问题吗?setContentView(R.layout.activity\u main)代码>此MainActivity布局您是否为WelcomeActivity定义了任何布局??