Question

我正在尝试传递一个字符串作为额外的，但由于某种原因它只是没有经历。这是我的代码：

public void setChordMajor(View v){
    chordType = "major";
    Intent intent = new Intent(this, ChordView.class);
    intent.putExtra("CHORD", chordType);
    startActivity(intent);
}

CHORD定义为：

public final static String CHORD = "com.example.musiciansreference.EXTRA_CHORD";

接下来的活动会收到它：

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_chord_view);

    Intent intent = getIntent();
    chordType = intent.getStringExtra(Chords.CHORD);

    TextView textView = new TextView(this);
    textView.setTextSize(40);
    textView.setText(chordType);

    setContentView(textView);
}

只显示一个空白屏幕。不知怎的，字符串没有被发送！

编辑：我认为问题在于第二个活动显示和弦的能力......这里是完整的代码：

import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.view.Menu; 
import android.view.MenuItem;
import android.widget.TextView;

public class ChordView extends ActionBarActivity {



String chordType = "null";

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_chord_view);

    Intent intent = getIntent();
    chordType = intent.getStringExtra(Chords.CHORD);

    TextView textView = new TextView(this);
    textView.setTextSize(40);
    textView.setText(chordType);

    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.chord_view, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();
    if (id == R.id.action_settings) {
        return true;
    }
    return super.onOptionsItemSelected(item);
}

}

Answer 1

intent.putExtra（Chords.CHORD，chordType）;而不是intent.putExtra（“CHORD”，chordType）;

Answer 2

以这种方式试试在xml布局中添加TextView元素，并从Oncreate方法中的ChordView引用它 TextView tv =（TextView）findviewbyId（R.id.tv）; Tv.setText（chordType）;看看空白屏幕是否仍然存在

在android中的活动之间传递额外内容

2 个答案: