我在我的应用程序中使用Dialog以允许用户进行多项选择,这是我的代码：
btn.setonClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// Build an AlertDialog
AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
// String array for alert dialog multi choice items
String[] colors = new String[]{
"Red","Green","Blue","Purple","Olive"
};
// Boolean array for initial selected items
final boolean[] checkedColors = new boolean[]{
false,// Red
false,// Green
false,// Blue
false,// Purple
false // Olive
};
// Convert the color array to list
final List<String> colorsList = Arrays.asList(colors);
// Set multiple choice items for alert dialog
builder.setMultiChoiceItems(colors,checkedColors,new DialogInterface.OnMultiChoiceClickListener() {
@Override
public void onClick(DialogInterface dialog,int which,boolean isChecked) {
// Update the current focused item's checked status
checkedColors[which] = isChecked;
// Get the current focused item
String currentItem = colorsList.get(which);
// Notify the current action
Toast.makeText(getApplicationContext(),currentItem + " " + isChecked,Toast.LENGTH_SHORT).show();
}
});
// Specify the dialog is not cancelable
builder.setCancelable(false);
// Set a title for alert dialog
builder.setTitle("Your preferred colors?");
// Set the positive/yes button click listener
builder.setPositiveButton("OK",new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog,int which) {
// Do something when click positive button
tv.setText("Your preferred colors..... \n");
for (int i = 0; i<checkedColors.length; i++){
boolean checked = checkedColors[i];
if (checked) {
tv.setText(tv.getText() + colorsList.get(i) + ",");
}
}
}
});
// Set the negative/no button click listener
builder.setNegativeButton("No",int which) {
// Do something when click the negative button
}
});
// Set the neutral/cancel button click listener
builder.setNeutralButton("Cancel",int which) {
// Do something when click the neutral button
}
});
AlertDialog dialog = builder.create();
// display the alert dialog on interface
dialog.show();
}
});
我有两个问题：
>就像我选择了红色和紫色
(然后在TextView中得到如下输出：红色,紫色,)
首先,我想删除逗号(获取最后一个值)
>我已经选择了红色和紫色,当我再次打开对话框时,默认情况下没有选择红色和紫色(我如何保存状态)在这里输入代码,结果,当我再次选择这些(红色和紫色)时两个项目,在TextView中获取每个项目两次
解决方法
尝试在循环后更新textview
如果你的循环迭代达到了checkedcolors的长度,那么就不要附加一个逗号.
public void onClick(DialogInterface dialog,int which) {
// Do something when click positive button
tv.setText("Your preferred colors..... \n");
for (int i = 0; i < checkedColors.length; i++) {
boolean checked = checkedColors[i];
String colors = "";
if (checked) {
colors = colors + colorsList.get(i) ;
if (i != checkedColors.length - 1) {
colors = colors + ",";
}
}
}
tv.setText(tv.getText() + colors);
}
Yor textview只会更新一次,因此您不会在TextView中两次获取每个项目.
要保存状态,您必须使用SharedPreference.
为了保存优先使用此功能
SharedPreferences preferences = mContext.getSharedPreferences("PREFERENCE_NAME",Context.MODE_PRIVATE);
SharedPreferences.Editor editor = preferences.edit();
editor.putBoolean("yourColor",isChecked);
editor.commit();
并检索
boolean isChecked = preferences.getBoolean("yourColor");