如何在Appcompat设置为27.1.0的情况下显示AlertDialog的正面和负面按钮

如何解决如何在Appcompat设置为27.1.0的情况下显示AlertDialog的正面和负面按钮

基于此build.gradle（：app）

apply plugin: 'com.android.application'
android {
    compileSdkVersion 27
    buildToolsVersion '27.0.3'
        ...
    }
    defaultConfig {
        applicationId "myapp"
        minSdkVersion 17
        targetSdkVersion 27
        ...
    }
    buildTypes {
            ...
    }
    productFlavors {
    }
}
dependencies {
        ...
    implementation 'com.android.support:appcompat-v7:23.4.0'
        ...
}

我有一个问题，appcompat的实现行用红色下划线标出，并有一条注释指出我们应将27.1.1版本替换为23.4.0。

当我更改为27.1.1时，问题出在AlertDialog上。使用setSingleChoiceItems且项目列表长于屏幕显示的内容时，不会出现正号和负号按钮。您可以滚动屏幕以查看所有项目，但是不存在肯定和否定按钮。如果该appcompat的版本为23.4.0，则显示按钮，并且AlertDialog窗口可以正常工作。

这是我的代码的一部分：

public void chooseFileOrDir(String dir) {
    File dirFile = new File(dir);
    while (!dirFile.exists() || !dirFile.isDirectory()) {
        dir = dirFile.getParent();
        dirFile = new File(dir);
    }
    try {
        dir = new File(dir).getCanonicalPath();
    } catch (IOException e) {
        Util.showMessage("chooseFileOrDir",e.toString());
        return;
    }
    mDir = dir;
    mFileList = getDirectories(dir);

    class SimpleFileDialogOnClickListener implements DialogInterface.OnClickListener {
        public void onClick(DialogInterface dialog,int item) {
            String oldDir = mDir;
            String sel = "" + ((AlertDialog) dialog).getListView().getAdapter().getItem(item);
            if (sel.charAt(sel.length() - 1) == '/')
                sel = sel.substring(0,sel.length() - 1);
            // Navigate into the sub-directory
            if (sel.equals("..")) {
                mDir = mDir.substring(0,mDir.lastIndexOf("/"));
                if ("".equals(mDir))
                    mDir = "/";
            } else
                mDir += "/" + sel;
            mSelectedFileName = mDefaultFileName;
            if (new File(mDir).isFile()) // If the selection is a regular file
            {
                mDir = oldDir;
                mSelectedFileName = sel;
            }
            mPathView.setText(mDir);
            ImageButton ParentDirButton = (ImageButton) ((AlertDialog) dialog).findViewById(BTN_DIR_PARENT);
            ParentDirButton.setVisibility(mDir.equals("/storage/emulated/0") ? View.INVISIBLE : View.VISIBLE);
            updateDirectory();
        }
    }
    AlertDialog.Builder dialogBuilder = createDirectoryChooserDialog(dir,mFileList,new SimpleFileDialogOnClickListener());
    dialogBuilder.setPositiveButton("OK",new OnClickListener() {
        @Override
        public void onClick(DialogInterface dialog,int which) {
            // Current directory chosen
            // Call registered listener supplied with the chosen directory
            if (mFileDialogListener != null) {
                if (mSelType == SEL_FILE) {
                    mSelectedFileName = mInputText.getText() + "";
                    if (mSelectedFileName.isEmpty())
                        dialog.dismiss();
                    else
                        mFileDialogListener.fileSelected(new File(mDir + "/" + mSelectedFileName));
                }
                else
                    mFileDialogListener.fileSelected(new File(mDir));
            }
        }
    }).setNegativeButton(Info.getContext().getResources().getString(R.string.CANCEL),null);
    final AlertDialog dirsDialog = dialogBuilder.create();
    // Show directory chooser dialog
    dirsDialog.show();
} //chooseFileOrDir

private AlertDialog.Builder createDirectoryChooserDialog(String title,List<Item> listItems,DialogInterface.OnClickListener onClickListener) {
    AlertDialog.Builder dialogBuilder = new AlertDialog.Builder(mContext);
    // Create custom view for AlertDialog title
    LinearLayout titleLayout1 = new LinearLayout(mContext);
    titleLayout1.setOrientation(LinearLayout.VERTICAL);
    // Create title text showing file select type //
    mTitleView = new TextView(mContext);
    mTitleView.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT,LayoutParams.WRAP_CONTENT));
    mTitleView.setGravity(Gravity.CENTER_HORIZONTAL);
    mTitleView.setPadding(0,15,0);
    mTitleView.setTextSize(25);
    if (mTitle != null && !mTitle.isEmpty())
        mTitleView.setText(mTitle);
    else if (mSelType == SEL_FILE)
        mTitleView.setText("Select a file:");
    else
        mTitleView.setText("Select a folder:");
    titleLayout1.addView(mTitleView);

    mPathView = new TextView(mContext);
    mPathView.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT,LayoutParams.WRAP_CONTENT));
    mPathView.setPadding(15,10,20);
    mPathView.setTextSize(15);
    mPathView.setText(mDir);
    titleLayout1.addView(mPathView);

    final ImageButton parentDirButton = new ImageButton(mContext);
    parentDirButton.setId(BTN_DIR_PARENT);
    parentDirButton.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT));
    parentDirButton.setBackgroundResource(R.mipmap.prev_folder);
    parentDirButton.setPadding(20,20,20);
    parentDirButton.setVisibility(mDir.equals("/storage/emulated/0") ? View.INVISIBLE : View.VISIBLE);

    parentDirButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            mDir = mDir.substring(0,mDir.lastIndexOf("/"));
            if ("".equals(mDir))
                mDir = "/";
            mSelectedFileName = "";
            updateDirectory();
            mPathView.setText(mDir);
            parentDirButton.setVisibility(mDir.equals("/storage/emulated/0") ? View.INVISIBLE : View.VISIBLE);
        }
    });
    titleLayout1.addView(parentDirButton);

    // Create View with folder path and entry text box //
    LinearLayout titleLayout = new LinearLayout(mContext);
    titleLayout.setOrientation(LinearLayout.VERTICAL);

    if (mSelType == SEL_FILE) {
        mInputText = new EditText(mContext);
        mInputText.setText(mDefaultFileName);
        titleLayout.addView(mInputText);
    }
    // Set Views and Finish Dialog builder
    dialogBuilder.setView(titleLayout);
    dialogBuilder.setCustomTitle(titleLayout1);
    mListAdapter = createListAdapter(listItems);
    dialogBuilder.setSingleChoiceItems(mListAdapter,-1,onClickListener);
    dialogBuilder.setCancelable(false);
    return dialogBuilder;
} // createDirectoryChooserDialog