我尝试搜索github，然后在这里搜索如何将项目添加到其他活动的列表视图中。
我目前正致力于我的学校项目，我需要做的是：
从其他活动中手动将项目添加到列表视图中（称为屏幕＆＃34;编辑屏幕＆＃34;）
我的问题是，当我添加电影时，它将始终覆盖我之前在列表视图中输入的电影
公共类MainActivity扩展了AppCompatActivity {
Button btnChooseScreen ;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//reading the sharedpref to popluate the listview
SharedPreferences save = getSharedPreferences("movie info" , MODE_PRIVATE);
final String movieName = save.getString("MOVIE NAME" , "defualt");
final String movieSummery = save.getString("MOVIE SUMMERY" , "defualt");
final String imageURL = save.getString("IMAGE URL" , "defualt");
final ArrayList<String> arrayOfMovies = new ArrayList<String>();
//arrayOfMovies.add(movieName);
btnChooseScreen= (Button) findViewById(R.id.btnChooseScreen);
btnChooseScreen.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
//make an alert dialog to ask the user which screen would he like to go
final AlertDialog.Builder adChooseScreen = new AlertDialog.Builder(MainActivity.this) ;
adChooseScreen.setTitle("WHAT TO DO?");
adChooseScreen.setPositiveButton("ADD MANUALLY", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialogInterface, int i) {
Intent intentToManualScreen = new Intent(MainActivity.this,EditScreen.class);
startActivity(intentToManualScreen);
}
});
adChooseScreen.setNeutralButton("ADD FROM THE INTERNET", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialogInterface, int i) {
Intent intentInternetScreen = new Intent(MainActivity.this , OnlineSearchScreen.class);
startActivity(intentInternetScreen);
}
});
adChooseScreen.show();
}
});
//will call the listView widget
final ListView myMovieListView = (ListView) findViewById(R.id.listView);
//to set the arrayList into the listView I need the component Adapter
final ArrayAdapter<String> myMoiveArrayAdapter = new ArrayAdapter<String>(MainActivity.this , android.R.layout.simple_list_item_1 ,arrayOfMovies );
myMovieListView.setAdapter(myMoiveArrayAdapter);
myMovieListView.setClickable(true);
myMoiveArrayAdapter.add(movieName);
myMoiveArrayAdapter.notifyDataSetChanged();
myMovieListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
Intent intentFromListViewToEditScreen = new Intent(MainActivity.this, EditScreen.class);
intentFromListViewToEditScreen.putExtra("movieName" ,movieName);
intentFromListViewToEditScreen.putExtra("movieSummary", movieSummery);
intentFromListViewToEditScreen.putExtra("imageUrl",imageURL);
startActivity(intentFromListViewToEditScreen);
}
});
}
//calling the menu and the menu inflater
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.menu , menu);
return super.onCreateOptionsMenu(menu);
}
//set what happens when cliking an item in the menu
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.settings :
//build an alert dialog for the option menu
final AlertDialog.Builder adOptionMenue = new AlertDialog.Builder(MainActivity.this) ;
//build an alert dialog for confirmation of deleting the list
final AlertDialog.Builder adbmakesure = new AlertDialog.Builder(MainActivity.this) ;
adOptionMenue.setTitle("SETTINGS") ;
//delete button
adOptionMenue.setPositiveButton("DELETE ALL ITEMS?", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
//making sure he didnt pressed delete by mistake
adbmakesure.setTitle("ARE YOU SURE YOU WANT TO DELETE ALL ITEMS?");
adbmakesure.setPositiveButton("YES", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialogInterface, int i) {
///////////////////////////////////
/////////WRITE DELETE CODE/////////
///////////////////////////////////
///////////////////////////////////
}
});
adbmakesure.setNeutralButton("NO TAKE ME BACK!", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialogInterface, int i) {
}
});
adbmakesure.show();
}
}) ;
//EXIT BUTTON
adOptionMenue.setNeutralButton("EXIT", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int which) {
//making sure he didnt pressed exit by mistake
adbmakesure.setTitle("CLOSE APPLICATION?");
adbmakesure.setPositiveButton("YES", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialogInterface, int i) {
System.exit(0);
}
});
adbmakesure.setNeutralButton("NO I WANT TO SEE MORE!", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialogInterface, int i) {
}
});
adbmakesure.show();
}
});
adOptionMenue.show();
return true ;
}
return super.onOptionsItemSelected(item);
这就是编辑屏幕
公共类EditScreen扩展了AppCompatActivity {
EditText etMovieName ;
EditText etMoviewSummery;
EditText etURL ;
@Override
protected void onCreate(final Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_edit_screen);
etMovieName = (EditText) findViewById(R.id.etMovieName);
// String inputMovieName = etMovieName.getText().toString();
etMoviewSummery = (EditText) findViewById(R.id.etSummery);
//String inputMovieSummery = etMoviewSummery.getText().toString();
etURL = (EditText) findViewById(R.id.etURL);
//String inputURL = etURL.getText().toString();
Button btnsave = (Button) findViewById(R.id.btnsave);
btnsave.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (etMovieName.getText().toString().isEmpty() || etMoviewSummery.getText().toString().isEmpty()
|| etURL.getText().toString().isEmpty()) {
Toast.makeText(EditScreen.this, "Must write details!!!", Toast.LENGTH_SHORT).show();
}
else {
Savedetails();
Intent intentgoback = new Intent(EditScreen.this, MainActivity.class);
startActivity(intentgoback);
}
}
});
//when item clicked at the mainactiveryscreen the details come from here
final String sMovieName= getIntent().getStringExtra("movieName");
final String sMovieSummery= getIntent().getStringExtra("movieSummary");
final String sURL= getIntent().getStringExtra("imageUrl");
if (sMovieName!=null && sMovieSummery !=null && sURL!=null ) {
etMovieName.setText(sMovieName);
etMoviewSummery.setText(sMovieSummery);
etURL.setText(sURL);
}
else {
}
}
//a method to save the info input
public void Savedetails() {
SharedPreferences save = getSharedPreferences("movie info", MODE_PRIVATE);
SharedPreferences.Editor edit = save.edit();
edit.putString("MOVIE NAME", etMovieName.getText().toString());
edit.putString("MOVIE SUMMERY", etMoviewSummery.getText().toString());
edit.putString("IMAGE URL", etURL.getText().toString());
edit.apply();
Toast.makeText(EditScreen.this, "DETAILS SAVED!", Toast.LENGTH_SHORT).show();
}
}
感谢您的帮助，祝您有个美好的一天：D
答案 0 :(得分：1)
您始终只在列表中放置一个项目 - 在onCreate中。永远不会添加第二个项目。 2个理由：
您在列表中设置了一个覆盖现有适配器的新适配器
当您返回时，您正在创建新活动。这是一个完整的新的，不包含任何内容，没有存储的列表项。它与您第一次启动活动时的状态基本相同。
我不会为你解决所有问题，因为你必须自己学习（这是一个学校项目;）），但我可以给你一些提示：