WALKのサンプル。テキストエリアの文字列を検索する。 ref. http://qiita.com/alucky0707/items/b066ccd2ff8517cf79fb

searchbox.exe.manifest

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
    <assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">
        <assemblyIdentity version="1.0.0.0" processorArchitecture="*" name="SomeFunkyNameHere" type="win32"/>
        <dependency>
            <dependentAssembly>
                <assemblyIdentity type="win32" name="Microsoft.Windows.Common-Controls" version="6.0.0.0" processorArchitecture="*" publicKeyToken="6595b64144ccf1df" language="*"/>
            </dependentAssembly>
        </dependency>
    </assembly>

searchbox.go

package main

//WALK関連のライブラリ
import (
    "github.com/lxn/walk"
    . "github.com/lxn/walk/declarative"
)

//その他標準ライブラリ
import (
    "fmt"
    "log"
    "strings"
)

func main() {
    mw := &MyMainWindow {}

    if _, err := (MainWindow {
        AssignTo: &mw.MainWindow,
        Title: "SearchBox",
        MinSize: Size {300, 400},
        Layout: VBox {},
        Children: []Widget {
            GroupBox {
                Layout: HBox {},
                Children: []Widget {
                    LineEdit {
                        AssignTo: &mw.searchBox,
                    },
                    PushButton {
                        Text: "検索",
                        OnClicked: mw.clicked,
                    },
                },
            },
            TextEdit {
                AssignTo: &mw.textArea,
            },
            ListBox {
                AssignTo: &mw.results,
                Row: 5,
            },
        },
    }.Run()); err != nil {
        log.Fatal(err)
    }

}

//structにまとめることで、グローバル変数を作らない
type MyMainWindow struct {
    *walk.MainWindow
    searchBox *walk.LineEdit
    textArea *walk.TextEdit
    results *walk.ListBox
}

func (mw *MyMainWindow) clicked() {
    word := mw.searchBox.Text()
    text := mw.textArea.Text()
    model := []string {}
    for _, i := range search(text, word) {
        model = append(model, fmt.Sprintf("%d文字目に発見", i))
    }
    log.Print(model)
    mw.results.SetModel(model)
}

//textからwordを検索して、位置をUnicode単位で返す
func search(text ,word string) (result []int) {
    result = []int {}
    i := 0
    for j, _ := range text {
        if strings.HasPrefix(text[j:], word) {
            log.Print(i)
            result = append(result, i)
        }
        i += 1
    }
    return
}