替换自定义对象的ArrayList中的值

Question

我有一个自定义类Distraction和一个使用ArrayAdapter显示Distracctions的ArrayList 单击列表中的各个项目后，将出现一个弹出菜单，其中包含“编辑”和“删除”选项 按下编辑时，会出现一个警告对话框，其中包含两个EditTexts，用于输入用户输入的名称和优先级 然后我想将用户输入与先前存储的值进行比较，如果不同则更新 但是，无论我在任何字段中输入什么，代码当前都会将名称更改为空白。

代码：

分心等级

public class Distraction {                                                                                 


//Distraction properties                                                                               
private String distraction_name;                                                                       
private String distraction_priority;                                                                   
private String distraction_occurance;                                                                  

//Constructor of Distraction type                                                                      
public Distraction (String distraction_name, String distraction_priority, String distraction_occurance)

    this.distraction_name = distraction_name;                                                          
    this.distraction_priority = distraction_priority;                                                  
    this.distraction_occurance = distraction_occurance;                                                
}                                                                                                      


//Getter methods                                                                                       

public String getDistraction_name(){return distraction_name;}                                          
public String getDistraction_priority(){return distraction_priority;}                                  
public String getDistraction_occurance(){return distraction_occurance;}                                

public void setDistraction_name(String distraction_name){                                              
    this.distraction_name = distraction_name;                                                          
}                                                                                                      

public void setDistraction_priority(String distraction_priority){                                      
    this.distraction_priority = distraction_priority;                                                  
}                                                                                                      

public void setDistraction_occurance(String distraction_occurance) {                                   
    this.distraction_occurance = distraction_occurance;                                                
}                                                                                                      
}                                                                                                          

我的活动代码

//Declare an Array List of Distractions
    final ArrayList<Distraction> distractionsArray = new ArrayList<>();

    //Creation of first sample data
    distractionsArray.add(new Distraction("Example: Text from Alice", "3", "1"));

    //Initialise the custom array adapter (nested ArrayAdapter class at the end of this activity)
    final ArrayAdapter<Distraction> adapter = new distractionArrayAdapter(DistractionsActivity.this, 0, distractionsArray );

    //Bind list view with the custom adapter
    distractions_list.setAdapter(adapter);

    //Adapter onclickable function
    distractions_list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, final int position, long id) {

            //Popup menu for distraction (EDIT, REMOVE)
            PopupMenu popup2 = new PopupMenu(DistractionsActivity.this, view);
            popup2.inflate(R.menu.distraction_menu);
            popup2.show();

            popup2.setOnMenuItemClickListener(new PopupMenu.OnMenuItemClickListener() {
                @Override
                public boolean onMenuItemClick(MenuItem item) {

                    //WHEN USER PRESSES EDIT
                    if (item.getItemId() == R.id.Edit) {

                        LayoutInflater dialog = LayoutInflater.from(DistractionsActivity.this);
                        final View edit_distraction_dialog_view = dialog.inflate(R.layout.edit_distractions, null);

                        //Create and initialise an AlertBuilder to open a pop-up where
                        //the user will be able to give some info about the distraction
                        final AlertDialog.Builder builder = new AlertDialog.Builder(DistractionsActivity.this);
                        builder.setTitle("Edit Distraction").setView(edit_distraction_dialog_view);

                        builder.setView(R.layout.edit_distractions);


                        //Set positive OK button for alert dialog
                        builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {
                                    @Override
                                    public void onClick(DialogInterface dialog, int which) {

                                        final EditText input_name = (EditText) edit_distraction_dialog_view.findViewById(R.id.edit_distraction_name_edittext);
                                        final EditText input_priority = (EditText) edit_distraction_dialog_view.findViewById(R.id.edit_distraction_priority_edittext);

                                        final String new_name = input_name.getText().toString();
                                        final String new_priority = input_priority.getText().toString();

                                        final String old_name = distractionsArray.get(position).getDistraction_name();
                                        final String old_priority = distractionsArray.get(position).getDistraction_priority();

                                        if (!(new_name.equals(old_name))){
                                            distractionsArray.get(position).setDistraction_name(new_name);
                                        }
                                        else
                                        {
                                            Toast.makeText(DistractionsActivity.this, "No input!", Toast.LENGTH_SHORT);
                                        }
                                        adapter.notifyDataSetChanged();
                                    }
                                });

                        //Set negative CANCEL button for the alert dialog
                        builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
                                @Override
                                public void onClick(DialogInterface dialog, int which) {
                                    //Close alert dialog
                                    dialog.cancel();
                                }
                            });
                        builder.show();
                    }
                    //WHEN USER PRESSES REMOVE
                    if (item.getItemId() == R.id.Remove) {
                        adapter.remove(distractionsArray.get(position));
                        adapter.notifyDataSetChanged();
                    }
                    return false;
                }
            });

        }
    });

它也不会在else语句中打印Toast。

有人可以解释为什么我的输入没有通过以及如何解决它？

Answer 1

因此，假设视图正确加载，此代码本身应该可以正常工作。

final EditText input_name = (EditText) edit_distraction_dialog_view.findViewById(R.id.edit_distraction_name_edittext);
final EditText input_priority = (EditText) edit_distraction_dialog_view.findViewById(R.id.edit_distraction_priority_edittext);

// You can debug and set breakpoints on these, though
final String new_name = input_name.getText().toString();
final String new_priority = input_priority.getText().toString();

如果你得到空字符串，那么有几种可能性

1）你没有打字。但是，我怀疑

2）对getText().toString()的调用并不等待您点击按钮。但是你在positive点击操作上这样做了。

3）您在另一个对话框的顶部加载了一个新视图。

似乎就是这种情况

// An inflater
LayoutInflater inflater = LayoutInflater.from(DistractionsActivity.this);
// An inflated View    
final View edit_distraction_dialog_view = inflater.inflate(R.layout.edit_distractions, null);

// A dialog
final AlertDialog.Builder builder = new AlertDialog.Builder(DistractionsActivity.this);
builder
    .setTitle("Edit Distraction")
    .setView(edit_distraction_dialog_view); // You already called setView!

// Don't need to call it again!
// builder.setView(R.layout.edit_distractions);

您可以将findViewById移到onClick

之外

builder.show(); // Need to call this first

final EditText input_name = (EditText) edit_distraction_dialog_view.findViewById(R.id.edit_distraction_name_edittext);
final EditText input_priority = (EditText) edit_distraction_dialog_view.findViewById(R.id.edit_distraction_priority_edittext);

//Set positive OK button for alert dialog
builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                String new_name = input_name.getText().toString();
                String new_priority = input_priority.getText().toString();