即使在使用 addView 之后，getChildCount() 总是返回 1

Question

我正在设计一个具有历史功能的简单计算器。之前的所有结果都以文本视图的形式存储，并使用 addView(childview) 添加到线性布局中。问题是，即使在将文本视图添加到线性布局之后，linearlayout.getChildCount() 始终返回 1。为简单起见，我将只在此处添加相关代码。

Calculator.java:

public class Calculator extends Fragment {
TextView resultTextView;
LinearLayout linearLayout;
ScrollView scrollView;
TextView et_temp, sign;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    return inflater.inflate (R.layout.fragment_calculator, container, false);
}

@Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
    super.onViewCreated (view, savedInstanceState);
    initControl(view);
    initControlListener();
    vibrator=(Vibrator) getActivity ().getSystemService (Context.VIBRATOR_SERVICE);
}

  private void initControlListener() {
    button0.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            onNumberButtonClicked("0");
        }
    });
    button1.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            onNumberButtonClicked("1");
        }
    });
    button2.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            onNumberButtonClicked("2");
        }
    });
    button3.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            onNumberButtonClicked("3");
        }
    });
    button4.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            onNumberButtonClicked("4");
        }
    });
    button5.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            onNumberButtonClicked("5");
        }
    });
    button6.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            onNumberButtonClicked("6");
        }
    });
    button7.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            onNumberButtonClicked("7");
        }
    });
    button8.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            onNumberButtonClicked("8");
        }
    });
    button9.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            onNumberButtonClicked("9");
        }
    });

    buttonClear.setOnLongClickListener (new View.OnLongClickListener () {
        @Override
        public boolean onLongClick(View view) {
            onClearHold ();
            return false;
        }
    });

    buttonClear.setOnClickListener (new View.OnClickListener () {
        @Override
        public void onClick(View view) {
            onClearButtonClicked ();

        }
    });

    buttonSubstract.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v){
            onOperatorButtonClicked("-");
        }
    });
    buttonAdd.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            onOperatorButtonClicked("+");
        }
    });
    buttonMul.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            onOperatorButtonClicked("X");
        }
    });
    buttonDiv.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            onOperatorButtonClicked("/");
        }
    });
    buttonEqual.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            onEqualButtonClicked();
        }
    });
    buttonDeci.setOnClickListener (new View.OnClickListener () {
        @Override
        public void onClick(View view) {
            onNumberButtonClicked (".");
        }
    });
    buttonReciprocal.setOnClickListener (new View.OnClickListener () {
        @Override
        public void onClick(View view) {
            onSpecialFunctionClick("Reci");
        }
    });
    buttonSqr.setOnClickListener (new View.OnClickListener () {
        @Override
        public void onClick(View view) {
            onSpecialFunctionClick("Sqr");
        }
    });
    buttonSqrRoot.setOnClickListener (new View.OnClickListener () {
        @Override
        public void onClick(View view) {
            onSpecialFunctionClick("SqrRoot");
        }
    });

    linearLayout.setOnLongClickListener (new View.OnLongClickListener () {
        @Override
        public boolean onLongClick(View view) {

            AlertDialog.Builder builder = new AlertDialog.Builder(getActivity ());
            builder.setMessage("Clear History?");
            builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {
                public void onClick(DialogInterface dialog, int id) {
                        scrollView.removeAllViews();
                        scrollView.setFillViewport (true);
                        scrollView.setClickable (true);
                }
            });
            builder.setNegativeButton ("Cancel", new DialogInterface.OnClickListener () {@Override
            public void onClick(DialogInterface dialogInterface, int i) {

            }
            });
            AlertDialog alert = builder.create();
            alert.show();

            return false;
        }
    });

}
//For adding history/views to linear layout
    public void createHistory(String str){
    if(!str.equals ("")) {
        et_temp = new TextView (getActivity ());
        et_temp.setGravity (Gravity.RIGHT);
        et_temp.setPadding (0, 5, 10, 5);
        et_temp.setTextColor (Color.rgb (50, 50, 50));
        et_temp.setTextSize (20);
        et_temp.setHovered (true);
        String x= sign.getText ().toString () + "   " + str;
        et_temp.setText (x);
        Log.e("dsfsd", (String.valueOf (scrollView.getChildCount ())));
        linearLayout.addView (et_temp);
    }

}

相关xml 文件fragment_calculator:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"

android:layout_width="match_parent"
android:layout_height="match_parent"
android:clickable="true"
android:background="?android:windowBackground"
android:orientation="vertical"
android:weightSum="1.0">

<ScrollView
    android:id="@+id/scroll_view"
    android:layout_width="match_parent"
    android:layout_height="0dp"
    android:layout_gravity="bottom"
    android:layout_weight="1"
    android:clickable="true"
    android:fillViewport="true">

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:clickable="false">

        <LinearLayout
            android:id="@+id/linear_layout"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_alignParentBottom="true"
            android:clickable="true"
            android:gravity="bottom"
            android:orientation="vertical">

        </LinearLayout>

    </RelativeLayout>
</ScrollView>
</LinearLayout>

Answer 1

您呼叫了 scrollView.getChildCount() 而不是 linearLayout.getChildCount()。