我无法在Visual Studio 2015（Android）中更改textView文本

Question

I am very new to Visual Studio. I'm required to create an android app with Visual Studio. I'm using Visual Studio 2015 Community.

Currently I have an android project with 2 activities (details and confirmation). In the details page, there are EditText for the user to input the details and in the confirmation page, a TextView is used to show the user input.

I have done this 2 activities, but when I run it, the confirmation page will be empty. I'm not sure whether my code is right or not.

There are few problems I encounter right now :-

• how to get the EditText value and assign it to variable
• how to pass the value from one activity to another
• how to read the value that is passed from the other activity
• how to change the TextView text

details.xml

<EditText
android:inputType="textMultiLine"
android:id="@+id/jobNumber"
android:layout_height="wrap_content" />

<EditText
android:inputType="textMultiLine"
android:id="@+id/statusCode"
android:layout_height="wrap_content" />

<EditText
android:inputType="textMultiLine"
android:id="@+id/statusDescription"
android:layout_height="wrap_content" />

<EditText
android:inputType="textMultiLine"
android:id="@+id/remarks"
android:layout_height="wrap_content" />

Details.cs

protected override void OnCreate(Bundle savedInstanceState)
{
    base.OnCreate(savedInstanceState);

    SetContentView(Resource.Layout.DetailsPage);

    EditText jn = FindViewById<EditText>(Resource.Id.jobNumber);
    EditText sc = FindViewById<EditText>(Resource.Id.statusCode);
    EditText sd = FindViewById<EditText>(Resource.Id.statusDescription);
    EditText r = FindViewById<EditText>(Resource.Id.remarks);

    String jobNum = jn.Text;
    String statusC = sc.Text;
    String statusD = sd.Text;
    String remarks = r.Text;

    Button next = FindViewById<Button>(Resource.Id.next);

    next.Click += delegate
    {
        Intent act = new Intent(this, typeof(Confirmation));

        act.PutExtra("jNum", jobNum);
        act.PutExtra("SC", statusC);
        act.PutExtra("SD", statusD);
        act.PutExtra("R", remarks);

        StartActivity(act);
    };
}

confirmation.xml

<TextView xmlns:tools="http://schemas.android.com/tools"    
    android:text="Medium Text"
    android:textAppearance="?android:attr/textAppearanceMedium"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:id="@+id/textView7" />
<TextView
    android:text="Medium Text"
    android:textAppearance="?android:attr/textAppearanceMedium"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:id="@+id/textView8" />
<TextView
    android:text="Medium Text"
    android:textAppearance="?android:attr/textAppearanceMedium"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:id="@+id/textView9" />
<TextView
    android:text="Medium Text"
    android:textAppearance="?android:attr/textAppearanceMedium"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:id="@+id/textView10" />

Confirmation.cs

protected override void OnCreate(Bundle savedInstanceState)
{
    base.OnCreate(savedInstanceState);

    SetContentView(Resource.Layout.Confirmation);

    String jobNumber = Intent.GetStringExtra("jNum");
    String statusCode = Intent.GetStringExtra("SC");
    String statusDescription = Intent.GetStringExtra("SD");
    String remarks = Intent.GetStringExtra("R");

    TextView jn = FindViewById<TextView>(Resource.Id.textView7b;
    TextView sc = FindViewById<TextView>(Resource.Id.textView8);
    TextView sd = FindViewById<TextView>(Resource.Id.textView9);
    TextView r = FindViewById<TextView>(Resource.Id.textView10);

    jn.Text = jobNumber;
    sc.Text = statusCode;
    sd.Text = statusDescription;
    r.Text = remarks;
}

Please help me, what do I do wrong? Why the TextView text does not change. Thank you so much in advance for those who try and solve this problem for me. APPRECIATE IT!

Regards, Azizi

Answer 1

You are trying to edit the Text variable directly, that is not possible. Use getText() and setText() instead.

For example:

Get text

String jobNum = jn.getText() ;

Set text

jn.setText(jobNumber)

Answer 2

Your error is that you are taken the texts when the Details activity starts, and obviously the text boxes are empty.

Put this:

String jobNum = jn.Text;
String statusC = sc.Text;
String statusD = sd.Text;
String remarks = r.Text;

Inside the button click delegate method.