Question

我想从Fragment Button打开另一个活动，但每次运行应用程序时，我都会不幸停止。

我已经这样做了一个星期仍然无法运行按钮。如果有人给我回答，我将不胜感激。我是android的新手。

我的代码是侧边菜单，然后其中一个侧边菜单包含用于打开新活动的按钮

package tipqc.softeng.sundroidtracker;

import android.app.Fragment;
import android.content.Intent;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.Button;

public class FindPeopleFragment extends Fragment{


View view;

//Intent i;

public FindPeopleFragment(){}

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {

    final View view = inflater.inflate(R.layout.fragment_find_people, container, false);

    Button button = (Button)view.findViewById(R.id.button1);
    button.setOnClickListener(new OnClickListener()
    {
        @Override
        public void onClick(View v){
            switch(v.getId()){

            case R.id.button1:
            Intent intent1 = new Intent(view.getContext(), ResearchStudy.class);
                startActivity(intent1);
                break;
            }
            //startActivity(i);
        }
    });

    return view;
}
}

以下是日志

12-31 14:36:33.040: E/AndroidRuntime(2843): FATAL EXCEPTION: main
12-31 14:36:33.040: E/AndroidRuntime(2843): Process: tipqc.softeng.sundroidtracker, PID: 2843
12-31 14:36:33.040: E/AndroidRuntime(2843): java.lang.RuntimeException: Unable to start activity ComponentInfo{tipqc.softeng.sundroidtracker/tipqc.softeng.sundroidtracker.ResearchStudy}: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
12-31 14:36:33.040: E/AndroidRuntime(2843):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2298)
12-31 14:36:33.040: E/AndroidRuntime(2843):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
12-31 14:36:33.040: E/AndroidRuntime(2843):     at android.app.ActivityThread.access$800(ActivityThread.java:144)
12-31 14:36:33.040: E/AndroidRuntime(2843):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
12-31 14:36:33.040: E/AndroidRuntime(2843):     at android.os.Handler.dispatchMessage(Handler.java:102)
12-31 14:36:33.040: E/AndroidRuntime(2843):     at android.os.Looper.loop(Looper.java:135)
12-31 14:36:33.040: E/AndroidRuntime(2843):     at android.app.ActivityThread.main(ActivityThread.java:5221)
12-31 14:36:33.040: E/AndroidRuntime(2843):     at java.lang.reflect.Method.invoke(Native Method)
12-31 14:36:33.040: E/AndroidRuntime(2843):     at java.lang.reflect.Method.invoke(Method.java:372)
12-31 14:36:33.040: E/AndroidRuntime(2843):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
12-31 14:36:33.040: E/AndroidRuntime(2843):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
12-31 14:36:33.040: E/AndroidRuntime(2843): Caused by: java.lang.IllegalStateException: You need to use a Theme.AppCompat theme (or descendant) with this activity.
12-31 14:36:33.040: E/AndroidRuntime(2843):     at android.support.v7.app.ActionBarActivityDelegate.onCreate(ActionBarActivityDelegate.java:110)
12-31 14:36:33.040: E/AndroidRuntime(2843):     at android.support.v7.app.ActionBarActivityDelegateICS.onCreate(ActionBarActivityDelegateICS.java:57)
12-31 14:36:33.040: E/AndroidRuntime(2843):     at android.support.v7.app.ActionBarActivity.onCreate(ActionBarActivity.java:99)
12-31 14:36:33.040: E/AndroidRuntime(2843):     at tipqc.softeng.sundroidtracker.ResearchStudy.onCreate(ResearchStudy.java:12)
12-31 14:36:33.040: E/AndroidRuntime(2843):     at android.app.Activity.performCreate(Activity.java:5933)
12-31 14:36:33.040: E/AndroidRuntime(2843):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
12-31 14:36:33.040: E/AndroidRuntime(2843):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2251)
12-31 14:36:33.040: E/AndroidRuntime(2843):     ... 10 more

Answer 1

尝试使用getActivity().startActivity()替换startActivity()方法，它会起作用！。

以下是完整的代码：

public FindPeopleFragment(){} 

@Override 
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {

    View view = inflater.inflate(R.layout.fragment_find_people, container, false);

    Button button = (Button)view.findViewById(R.id.button1);
    button.setOnClickListener(new OnClickListener()
    { 
        @Override 
        public void onClick(View v){
            switch(v.getId()){

            case R.id.button1:
                Intent intent1 = new Intent(getActivity(), ResearchStudy.class);
                startActivity(intent1);//Edited here
                break; 


            } 
        } 
    }); 

    return view;
}

希望这有帮助！

Answer 2

你必须写下面的代码行来从片段开始活动：

Intent intent = new Intent(getActivity(), ActivityB.class);
startActivity(intent);

Answer 3

public FindPeopleFragment(){} 
 View view;
 @Override 
  public View onCreateView(LayoutInflater inflater, ViewGroup container,
    Bundle savedInstanceState) {

view = inflater.inflate(R.layout.fragment_find_people, container, false);

Button button = (Button)view.findViewById(R.id.button1);
button.setOnClickListener(new OnClickListener()
{ 
    @Override 
    public void onClick(View v){
        switch(v.getId()){

        case R.id.button1:
            Intent intent1 = new Intent(view.getContext(), ResearchStudy.class);
            view.getContext().startActivity(intent1);
            break; 


        } 
    } 
}); 

return view;

}

Answer 4

如何使用片段内的按钮启动另一个活动

此答案最适合android中的Navigation Drawble

清单

//设置新Java类的路径，该Java类在片段类的Intent下定义

 <activity android:name="com.example.mysqlinsert.ui.settings.setLayouts"></activity>

在片段类中使用Intent的类


public class setLayouts extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView( R.layout.about); 
//layout name which you need to set using onClickListner
    }
}

片段Java类

public class SettingFragment extends Fragment {

    public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

         View root =  inflater.inflate( R.layout.fragment_layoutName, container, false );

        Button about = (Button) root.findViewById(R.id.about);

        about.setOnClickListener( new View.OnClickListener() {
            public void onClick(View v) {
                Intent intent = new Intent( getContext(), requiredJavaClassName.class );
                startActivity( intent );
            }

        } );
        return root;
    }
}````

如何使用Fragment中的Button启动另一个Activity

4 个答案: