Start Activity with Button Android

问题:

Ive got a problem. I want to open an Activity with a Button but it crashes all the time. So I created 2 Classes and A Button. But it keeps crashing.

1. Class is activity_home class() and second is schedule_act() class.

activity_home class:

    package my.action.bat;

    import android.app.Activity;
    import android.content.Intent;
    import android.os.Bundle;
    import android.view.View;
    import android.widget.Button;

    public class activity_home extends Activity {

        private Button ScheduleBtn;

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            // TODO Auto-generated method stub
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);

             ScheduleBtn = (Button) findViewById(R.id.home_btn_schedule);

            ScheduleBtn.setOnClickListener(new View.OnClickListener() {

                public void onClick(View v) {
                    // TODO Auto-generated method stub


                    Intent myIntent = new Intent("my.action.bat.schedule_act");
                    startActivity(myIntent);


                }
            });
        }





    }  

schedule_act class:

package my.action.bat;

    import android.app.Activity;
    import android.os.Bundle;

    public class schedule_act extends Activity {

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            // TODO Auto-generated method stub
            super.onCreate(savedInstanceState);

            setContentView(R.layout.schedule_layout);
        }



    }

Android Manifest:

    <?xml version="1.0" encoding="utf-8"?>
    <manifest xmlns:android="http://schemas.android.com/apk/res/android"
        package="my.action.bat"
        android:versionCode="1"
        android:versionName="1.0" >

        <uses-sdk android:minSdkVersion="8" />

        <application
            android:icon="@drawable/ic_launcher"
            android:label="@string/app_name" >
            <activity
                android:label="@string/app_name"
                android:name=".activity_home" >
                <intent-filter >
                    <action android:name="android.intent.action.MAIN" />

                    <category android:name="android.intent.category.LAUNCHER" />
                </intent-filter>
            </activity>

            <activity
                android:label="@string/app_name"
                android:name=".schedule_act" >
                <intent-filter >
                    <action android:name="my.action.bat.SCHEDULE_ACT" />

                    <category android:name="android.intent.category.DEFAULT" />
                </intent-filter>
            </activity>
        </application>

    </manifest>  

Thank you very much.

回答1:

Intents are case sensitive. Change

"my.action.bat.schedule_act"

To

"my.action.bat.SCHEDULE_ACT"

Also, unless you really need to use an intent, I would start your activity like so

startActivity(new Intent(this, schedule_act.class));

Where this is a Context subclass

回答2:

Try this

localIntent = new Intent(activity_home.this, schedule_act.class);
    activity_home.this.startActivity(localIntent);

回答3:

Try changing the line

 Intent myIntent = new Intent("my.action.bat.schedule_act");

To

 Intent myIntent = new Intent(v.getContext(), schedule_act.class);

And see if that helps.

See here for more info.

回答4:

You can change this line

Intent myIntent = new Intent("my.action.bat.schedule_act"); startActivity(myIntent);

To something like this

Intent intent = new Intent ("Your context", "Your activity to launch"); startActivity(intent);

Remember always especify a context and a activity.

回答5:

You have to add all the activity classes to the manifest file!!