在我的 Android 活动中，我有一个EditText、一个“ + ”按钮、一个“ - ”按钮、“ Save ”按钮和“ Load ”按钮。当我按“ + ”时，EditText中的值增加 1，类似地在按“ - ”时值减少 1。我曾经SharedPreferences在单击“保存”时保存数据。当我单击“加载”时，我想将此数据重新加载到EditText字段中。
现在的问题是，当我完全退出应用程序（即使是最近使用的应用程序）并单击“加载”重新启动它时，保存的号码不会出现。我在方法中包含onClick()了“加载”方法的操作onRestart()。它仍然不起作用。我在这里想念什么？我什至针对之前在这里提出的类似问题尝试了所有其他建议。另外，是真的onRestart()还是onRestoreInstanceState()？
public class MainActivity extends Activity {
Button btn1;
Button btn2;
Button btn3;
Button btn4;
EditText scoreText;
int counter = 0;
TextView textTitle;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btn1 = (Button)findViewById(R.id.add);
btn2 = (Button)findViewById(R.id.subtract);
btn3 = (Button)findViewById(R.id.save);
btn4 = (Button)findViewById(R.id.load);
scoreText = (EditText)findViewById(R.id.total);
textTitle = (TextView)findViewById(R.id.title);
btn1.setOnClickListener(new View.OnClickListener() {
// The code in this method will be executed when the numbers View is clicked on.
@Override
public void onClick(View v) {
counter++;
scoreText.setText(Integer.toString(counter));
scoreText.setBackgroundColor(Color.GREEN);
}
});
btn2.setOnClickListener(new View.OnClickListener() {
// The code in this method will be executed when the numbers View is clicked on.
@Override
public void onClick(View v) {
counter=counter-1;
scoreText.setText(Integer.toString(counter));
scoreText.setBackgroundColor(Color.RED);
}
});
btn3.setOnClickListener(new View.OnClickListener() {
// The code in this method will be executed when the numbers View is clicked on.
@Override
public void onClick(View v) {
//store data using sharedprefernces
SharedPreferences sharedPreferences=getSharedPreferences("Data", Context.MODE_PRIVATE);
SharedPreferences.Editor editor=sharedPreferences.edit();
//Edit method allow to write the data in sharedpreferences
editor.putString("count",scoreText.getText().toString());
//For commit changes commit() method is used
editor.commit();
Toast.makeText(getApplicationContext(),"Data Saved",Toast.LENGTH_SHORT).show();
}
});
btn4.setOnClickListener(new View.OnClickListener() {
// The code in this method will be executed when the numbers View is clicked on.
@Override
public void onClick(View v) {
SharedPreferences sharedPreferences=getSharedPreferences("Data", Context.MODE_PRIVATE);
String strcount=sharedPreferences.getString("name",scoreText.getText().toString());
// scoreText.setText(strcount);
scoreText.setBackgroundColor(Color.YELLOW);
}
});
}
@Override
protected void onRestart(Bundle savedInstanceState){
super.onRestart(savedInstanceState);
btn4.setOnClickListener(new View.OnClickListener() {
// The code in this method will be executed when the numbers View is clicked on.
@Override
public void onClick(View v) {
SharedPreferences sharedPreferences=getSharedPreferences("Data", Context.MODE_PRIVATE);
String strcount=sharedPreferences.getString("name",scoreText.getText().toString());
if (strcount.equals(""))
{
Toast.makeText(getApplicationContext(), "Data Was Not Found", Toast.LENGTH_SHORT).show();
}
else
{
scoreText.setText(strcount);
}
scoreText.setBackgroundColor(Color.YELLOW);
}
});
}