我已经根据建议进行了更改,但它工作正常。但我已将按钮mainactivity移至main2activity以检查列表,但它给出了错误。 这是我的代码和按钮,检查列表R.Id.viewlist保存列表中的项目
public class MainActivity extends AppCompatActivity {
EditText editText;
Button addButton;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
final EditText editText =(EditText)findViewById(R.id.editText);
Button button = (Button)findViewById(R.id.addButton);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this,Main2Activity.class);
intent.putExtra("text", editText.getText().toString());
startActivity(intent);
}
});
Button button1 = (Button)findViewById(R.id.viewlist);
button1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this,Main2Activity.class);
startActivity(intent);
}
});
main2acctivity
public class Main2Activity extends AppCompatActivity {
ListView listView;
ArrayAdapter<String> adapter;
@Override
protected void onRestart() {
super.onRestart();
adapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1, Global.list1);
listView.setAdapter(adapter);
if (Global.list1.size()<1){
Global.list1=new ArrayList<>();
}
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main2);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
Intent intent1= getIntent();
listView = (ListView) findViewById(R.id.list);
adapter = new ArrayAdapter<String>(this,android.R.layout.simple_list_item_1, Global.list1);
listView.setAdapter(adapter);
Global.list1.add(intent1.getStringExtra("text"));
adapter.notifyDataSetChanged();
}
全球。类
创建一个全球arraylist并添加项目,以便您的列表将自动更新当您更新arraylist – Mohit
我是新来的Android可以帮助我与如何创建全局数组list.please –
是的肯定...有一看我的[这](http://stackoverflow.com/a/35183420/2553431)答案..这是similer你的问题....后,如果你仍然面临问题.... – Mohit